Fails to source "logstash.lib.sh" when starting over SSH

Hi, I'm trying to start logstash and detach as a SSH one-liner in a remote management script. I get the following error when running `ssh user@host cd path/to/logstash && bin/logstash`

```
bin/logstash: $(cd bin/..; pwd)/bin/logstash.lib.sh: not found
```

When I run the command in an interactive SSH session I also get the above error.

Please note that I'm running this on a Windows machine, and pointing to a SunOS VM. I tried using Logstash 1.5.4 and the latest 2.0.0.beta1 and encountered the same issue.

EDIT : bumping this up a bit. :)
EDIT 2 : actually, I do get this error when running in an interactive session...

Start with bin/logstash and the referenced logstash.lib.sh path, then reproduce the failure using the SSH command against the SunOS VM. Compare the remote and interactive startup behavior and verify that Logstash starts successfully over SSH without the sourcing error.

Written by the indexing model from the issue text.