Setup periodically fails to completely download jar

When pip installing the python client, the installation will complete successfully, but we end up with an empty amazon-kinesis-client-1.9.0.jar.
```
$ ls -la /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars/amazon-kinesis-client-1.9.0.jar

-rw-r--r-- 1 root staff 0 Apr 11 12:31 /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars/amazon-kinesis-client-1.9.0.jar
```
Note: This happens maybe 1/30 installations.

```
$ grep -C 5 amazon-kinesis-client /var/log/cloud-init-output.log

Running setup.py install for amazon-kclpy: started
Running command /usr/bin/python -u -c "import setuptools, tokenize;__file__='/tmp/pip-build-64l3ox/amazon-kclpy/setup.py';f=getattr(tokenize, 'open', open)(__file__);code=f.read().replace('\r\n', '\n');f.close();exec(compile(code, __file__, 'exec'))" install --record /tmp/pip-cpcXRc-record/install-record.txt --single-version-externally-managed --compile
running install
Attempting to retrieve remote jar http://search.maven.org/remotecontent?filepath=com/amazonaws/amazon-kinesis-client/1.9.0/amazon-kinesis-client-1.9.0.jar
Saving http://search.maven.org/remotecontent?filepath=com/amazonaws/amazon-kinesis-client/1.9.0/amazon-kinesis-client-1.9.0.jar -> amazon_kclpy/jars/amazon-kinesis-client-1.9.0.jar
Attempting to retrieve remote jar http://search.maven.org/remotecontent?filepath=com/amazonaws/aws-java-sdk-dynamodb/1.11.272/aws-java-sdk-dynamodb-1.11.272.jar
Saving http://search.maven.org/remotecontent?filepath=com/amazonaws/aws-java-sdk-dynamodb/1.11.272/aws-java-sdk-dynamodb-1.11.272.jar -> amazon_kclpy/jars/aws-java-sdk-dynamodb-1.11.272.jar
Attempting to retrieve remote jar http://search.maven.org/remotecontent?filepath=com/amazonaws/aws-java-sdk-s3/1.11.272/aws-java-sdk-s3-1.11.272.jar
Saving http://search.maven.org/remotecontent?filepath=com/amazonaws/aws-java-sdk-s3/1.11.272/aws-java-sdk-s3-1.11.272.jar -> amazon_kclpy/jars/aws-java-sdk-s3-1.11.272.jar
Attempting to retrieve remote jar http://search.maven.org/remotecontent?filepath=com/amazonaws/aws-java-sdk-kms/1.11.272/aws-java-sdk-kms-1.11.272.jar
--
copying amazon_kclpy/jars/ion-java-1.0.2.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying amazon_kclpy/jars/httpclient-4.5.2.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying amazon_kclpy/jars/jackson-dataformat-cbor-2.6.7.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying amazon_kclpy/jars/commons-lang-2.6.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying amazon_kclpy/jars/aws-java-sdk-cloudwatch-1.11.272.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying amazon_kclpy/jars/amazon-kinesis-client-1.9.0.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying amazon_kclpy/jars/aws-java-sdk-kinesis-1.11.272.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying amazon_kclpy/jars/protobuf-java-2.6.1.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying amazon_kclpy/jars/aws-java-sdk-core-1.11.272.jar -> build/lib.linux-x86_64-2.7/amazon_kclpy/jars
copying samples/sample.properties -> build/lib.linux-x86_64-2.7/samples
running build_scripts
--
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/ion-java-1.0.2.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/httpclient-4.5.2.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/jackson-dataformat-cbor-2.6.7.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/commons-lang-2.6.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/aws-java-sdk-cloudwatch-1.11.272.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/amazon-kinesis-client-1.9.0.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/aws-java-sdk-kinesis-1.11.272.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/protobuf-java-2.6.1.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
copying build/lib.linux-x86_64-2.7/amazon_kclpy/jars/aws-java-sdk-core-1.11.272.jar -> /usr/local/lib/python2.7/dist-packages/amazon_kclpy/jars
creating /usr/local/lib/python2.7/dist-packages/samples

```

Nothing in the verbose output is indicating that the download or copy is failing, so I'm really not sure what to suggest. But it would be nice if there was some kind of validation step and the installation would fail if the validation failed.