ENV not propagated to process-wrapper

Please provide the following information. The more we know about your system and use case, the more easily and likely we can help.

### Description of the problem / feature request / question:
I have a problem using bazel to build the rules_scala on a custom platform. I am sure it is because the shell envs are not propagated correctly to a subprocess that is spawned by some actions of bazel. Please see the log information that I provide in the last section.

### If possible, provide a minimal example to reproduce the problem:

### Environment info
* Operating System:
CentOS 6.7

* Bazel version (output of `bazel info release`):
0.5.4

* If `bazel info release` returns "development version" or "(@non-git)", please tell us what source tree you compiled Bazel from; git commit hash is appreciated (`git rev-parse HEAD`):

### Have you found anything relevant by searching the web?
(e.g. [StackOverflow answers](http://stackoverflow.com/questions/tagged/bazel),
[GitHub issues](https://github.com/bazelbuild/bazel/issues),
email threads on the [`bazel-discuss`](https://groups.google.com/forum/#!forum/bazel-discuss) Google group)

### Anything else, information or logs or outputs that would be helpful?
(If they are large, please upload as attachment or provide link).

The command I ran to build rules_scala is `bazel build -s --verbose_failures --sandbox_debug //src/...`

```
>>>>> # //src/scala/io/bazel/rules_scala/tut_support:tut_compiler [action 'scala //src/scala/io/bazel/rules_scala/tut_support:tut_compiler']
(cd /home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala && \
exec env - \
/bin/bash -c '
rm -f bazel-out/local-fastbuild/bin/src/scala/io/bazel/rules_scala/tut_support/tut_compiler.jar
external/bazel_tools/tools/zip/zipper/zipper c bazel-out/local-fastbuild/bin/src/scala/io/bazel/rules_scala/tut_support/tut_compiler.jar @bazel-out/local-fastbuild/bin/src/scala/io/bazel/rules_scala/tut_support/bazel-out/local-fastbuild/bin/src/scala/io/bazel/rules_scala/tut_support/tut_compiler.jar_zipper_args
')
>>>>> # @scala//:scala-reflect [action 'Extracting interface @scala//:scala-reflect [for host]']
(cd /home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala && \
exec env - \
LD_LIBRARY_PATH=/cm/shared/gcc/6.4.0/lib64:/cm/shared/gcc/6.4.0/lib:/cm/shared/apps/mpc/1.0.3/lib:/cm/shared/apps/gcc/4.9.2/gmp-6.0/lib:/cm/shared/apps/mpfr/3.1.3/lib:/cm/shared/apps/sqlite3/3.15.0/lib:/cm/shared/apps/libevent/2.1.5-beta/lib:/cm/shared/apps/cudnn/6.0/lib64:/cm/shared/apps/java/jdk1.8.0_112/lib:/cm/shared/apps/python/3.6.0/lib:/cm/shared/apps/cuda/8.0/lib64:/cm/shared/apps/binutils/2.25/src/lib:/cm/shared/apps/slurm/current/lib/slurm:/cm/shared/apps/slurm/current/lib:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/compiler/lib/intel64:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/mkl/lib/intel64:/home-4/yliu120@jhu.edu/lib:/home-4/yliu120@jhu.edu/opt/lib \
PATH=/cm/shared/gcc/6.4.0/bin:/home-4/yliu120@jhu.edu/go/bin:/home-4/yliu120@jhu.edu/.local/bin:/home-4/yliu120@jhu.edu/opt/go/bin:/home-4/yliu120@jhu.edu/maven/bin:/home-4/yliu120@jhu.edu/arcanist/bin:/home-4/yliu120@jhu.edu/opt/bin:/cm/shared/apps/sqlite3/3.15.0/bin:/cm/shared/apps/tmux/2.1/bin:/cm/shared/apps/libevent/2.1.5-beta/bin:/cm/shared/apps/java/jdk1.8.0_112/bin:/cm/shared/apps/python/3.6.0/bin:/cm/shared/apps/cuda/8.0/bin:/cm/shared/apps/binutils/2.25/src/bin:/cm/shared/apps/binutils:/cm/shared/apps/slurm/current/sbin:/cm/shared/apps/slurm/current/bin:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/bin/intel64:/usr/lib64/qt-3.3/bin:/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin:/opt/ibutils/bin:/sbin:/usr/sbin:/cm/local/apps/environment-modules/3.2.10/bin:/opt/dell/srvadmin/bin \
external/bazel_tools/tools/jdk/ijar/ijar external/scala/lib/scala-reflect.jar bazel-out/host/genfiles/external/scala/_ijar/scala-reflect/external/scala/lib/scala-reflect-ijar.jar)
>>>>> # @scala//:scala-reflect [action 'Extracting interface @scala//:scala-reflect']
(cd /home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala && \
exec env - \
LD_LIBRARY_PATH=/cm/shared/gcc/6.4.0/lib64:/cm/shared/gcc/6.4.0/lib:/cm/shared/apps/mpc/1.0.3/lib:/cm/shared/apps/gcc/4.9.2/gmp-6.0/lib:/cm/shared/apps/mpfr/3.1.3/lib:/cm/shared/apps/sqlite3/3.15.0/lib:/cm/shared/apps/libevent/2.1.5-beta/lib:/cm/shared/apps/cudnn/6.0/lib64:/cm/shared/apps/java/jdk1.8.0_112/lib:/cm/shared/apps/python/3.6.0/lib:/cm/shared/apps/cuda/8.0/lib64:/cm/shared/apps/binutils/2.25/src/lib:/cm/shared/apps/slurm/current/lib/slurm:/cm/shared/apps/slurm/current/lib:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/compiler/lib/intel64:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/mkl/lib/intel64:/home-4/yliu120@jhu.edu/lib:/home-4/yliu120@jhu.edu/opt/lib \
PATH=/cm/shared/gcc/6.4.0/bin:/home-4/yliu120@jhu.edu/go/bin:/home-4/yliu120@jhu.edu/.local/bin:/home-4/yliu120@jhu.edu/opt/go/bin:/home-4/yliu120@jhu.edu/maven/bin:/home-4/yliu120@jhu.edu/arcanist/bin:/home-4/yliu120@jhu.edu/opt/bin:/cm/shared/apps/sqlite3/3.15.0/bin:/cm/shared/apps/tmux/2.1/bin:/cm/shared/apps/libevent/2.1.5-beta/bin:/cm/shared/apps/java/jdk1.8.0_112/bin:/cm/shared/apps/python/3.6.0/bin:/cm/shared/apps/cuda/8.0/bin:/cm/shared/apps/binutils/2.25/src/bin:/cm/shared/apps/binutils:/cm/shared/apps/slurm/current/sbin:/cm/shared/apps/slurm/current/bin:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/bin/intel64:/usr/lib64/qt-3.3/bin:/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin:/opt/ibutils/bin:/sbin:/usr/sbin:/cm/local/apps/environment-modules/3.2.10/bin:/opt/dell/srvadmin/bin \
external/bazel_tools/tools/jdk/ijar/ijar external/scala/lib/scala-reflect.jar bazel-out/local-fastbuild/genfiles/external/scala/_ijar/scala-reflect/external/scala/lib/scala-reflect-ijar.jar)
>>>>> # @scala//:scala-compiler [action 'Extracting interface @scala//:scala-compiler']
(cd /home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala && \
exec env - \
LD_LIBRARY_PATH=/cm/shared/gcc/6.4.0/lib64:/cm/shared/gcc/6.4.0/lib:/cm/shared/apps/mpc/1.0.3/lib:/cm/shared/apps/gcc/4.9.2/gmp-6.0/lib:/cm/shared/apps/mpfr/3.1.3/lib:/cm/shared/apps/sqlite3/3.15.0/lib:/cm/shared/apps/libevent/2.1.5-beta/lib:/cm/shared/apps/cudnn/6.0/lib64:/cm/shared/apps/java/jdk1.8.0_112/lib:/cm/shared/apps/python/3.6.0/lib:/cm/shared/apps/cuda/8.0/lib64:/cm/shared/apps/binutils/2.25/src/lib:/cm/shared/apps/slurm/current/lib/slurm:/cm/shared/apps/slurm/current/lib:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/compiler/lib/intel64:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/mkl/lib/intel64:/home-4/yliu120@jhu.edu/lib:/home-4/yliu120@jhu.edu/opt/lib \
PATH=/cm/shared/gcc/6.4.0/bin:/home-4/yliu120@jhu.edu/go/bin:/home-4/yliu120@jhu.edu/.local/bin:/home-4/yliu120@jhu.edu/opt/go/bin:/home-4/yliu120@jhu.edu/maven/bin:/home-4/yliu120@jhu.edu/arcanist/bin:/home-4/yliu120@jhu.edu/opt/bin:/cm/shared/apps/sqlite3/3.15.0/bin:/cm/shared/apps/tmux/2.1/bin:/cm/shared/apps/libevent/2.1.5-beta/bin:/cm/shared/apps/java/jdk1.8.0_112/bin:/cm/shared/apps/python/3.6.0/bin:/cm/shared/apps/cuda/8.0/bin:/cm/shared/apps/binutils/2.25/src/bin:/cm/shared/apps/binutils:/cm/shared/apps/slurm/current/sbin:/cm/shared/apps/slurm/current/bin:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/bin/intel64:/usr/lib64/qt-3.3/bin:/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin:/opt/ibutils/bin:/sbin:/usr/sbin:/cm/local/apps/environment-modules/3.2.10/bin:/opt/dell/srvadmin/bin \
external/bazel_tools/tools/jdk/ijar/ijar external/scala/lib/scala-compiler.jar bazel-out/local-fastbuild/genfiles/external/scala/_ijar/scala-compiler/external/scala/lib/scala-compiler-ijar.jar)
>>>>> # @io_bazel_rules_scala_org_tpolecat_tut_core//jar:jar [action 'Extracting interface @io_bazel_rules_scala_org_tpolecat_tut_core//jar:jar']
(cd /home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala && \
exec env - \
LD_LIBRARY_PATH=/cm/shared/gcc/6.4.0/lib64:/cm/shared/gcc/6.4.0/lib:/cm/shared/apps/mpc/1.0.3/lib:/cm/shared/apps/gcc/4.9.2/gmp-6.0/lib:/cm/shared/apps/mpfr/3.1.3/lib:/cm/shared/apps/sqlite3/3.15.0/lib:/cm/shared/apps/libevent/2.1.5-beta/lib:/cm/shared/apps/cudnn/6.0/lib64:/cm/shared/apps/java/jdk1.8.0_112/lib:/cm/shared/apps/python/3.6.0/lib:/cm/shared/apps/cuda/8.0/lib64:/cm/shared/apps/binutils/2.25/src/lib:/cm/shared/apps/slurm/current/lib/slurm:/cm/shared/apps/slurm/current/lib:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/compiler/lib/intel64:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/mkl/lib/intel64:/home-4/yliu120@jhu.edu/lib:/home-4/yliu120@jhu.edu/opt/lib \
PATH=/cm/shared/gcc/6.4.0/bin:/home-4/yliu120@jhu.edu/go/bin:/home-4/yliu120@jhu.edu/.local/bin:/home-4/yliu120@jhu.edu/opt/go/bin:/home-4/yliu120@jhu.edu/maven/bin:/home-4/yliu120@jhu.edu/arcanist/bin:/home-4/yliu120@jhu.edu/opt/bin:/cm/shared/apps/sqlite3/3.15.0/bin:/cm/shared/apps/tmux/2.1/bin:/cm/shared/apps/libevent/2.1.5-beta/bin:/cm/shared/apps/java/jdk1.8.0_112/bin:/cm/shared/apps/python/3.6.0/bin:/cm/shared/apps/cuda/8.0/bin:/cm/shared/apps/binutils/2.25/src/bin:/cm/shared/apps/binutils:/cm/shared/apps/slurm/current/sbin:/cm/shared/apps/slurm/current/bin:/cm/shared/apps/parallel_studio_xe_2015_update2/composer_xe_2015.2.164/bin/intel64:/usr/lib64/qt-3.3/bin:/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin:/opt/ibutils/bin:/sbin:/usr/sbin:/cm/local/apps/environment-modules/3.2.10/bin:/opt/dell/srvadmin/bin \
external/bazel_tools/tools/jdk/ijar/ijar external/io_bazel_rules_scala_org_tpolecat_tut_core/jar/tut-core_2.11-0.4.8.jar bazel-out/local-fastbuild/genfiles/external/io_bazel_rules_scala_org_tpolecat_tut_core/jar/_ijar/jar/external/io_bazel_rules_scala_org_tpolecat_tut_core/jar/tut-core_2.11-0.4.8-ijar.jar)
ERROR: /home-4/yliu120@jhu.edu/rules_scala/src/scala/scripts/BUILD:41:1: error executing shell command: '
rm -f bazel-out/local-fastbuild/bin/src/scala/scripts/scalapb_generator.jar
external/bazel_tools/tools/zip/zipper/zipper c bazel-out/local-fastbuild/bin/src/scala/scripts/scalapb_generator.jar @ba...' failed (Exit 1): process-wrapper failed: error executing command
(cd /home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala && \
exec env - \
/home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala/_bin/process-wrapper '--timeout=-1' '--kill_delay=15' /bin/bash -c '
rm -f bazel-out/local-fastbuild/bin/src/scala/scripts/scalapb_generator.jar
external/bazel_tools/tools/zip/zipper/zipper c bazel-out/local-fastbuild/bin/src/scala/scripts/scalapb_generator.jar @bazel-out/local-fastbuild/bin/src/scala/scripts/bazel-out/local-fastbuild/bin/src/scala/scripts/scalapb_generator.jar_zipper_args
').
/home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala/_bin/process-wrapper: /usr/lib64/libstdc++.so.6: version `GLIBCXX_3.4.21' not found (required by /home-4/yliu120@jhu.edu/.cache/bazel/_bazel_yliu120@jhu.edu/12dd3863654b107695e643fa774ca856/execroot/io_bazel_rules_scala/_bin/process-wrapper)
INFO: Elapsed time: 0.820s, Critical Path: 0.14s
```
From the log message, you can see the first command doesn't have PATH and LD_LIBRARY_PATH propagated but the others have.

Reproduce the failure from the issue with Bazel 0.5.4 on CentOS 6.7, using the `bazel build -s --verbose_failures --sandbox_debug //src/...` command and the `src/scala/scripts/BUILD:41` action. Start by examining the `_bin/process-wrapper` entry point and comparing the environment shown for each command. Done means the affected subprocess receives the required environment and the build no longer fails with the GLIBCXX error.

Written by the indexing model from the issue text.