Update travis config to install protobuf-compiler
Run 'mvn install' in top-level directory to build test apps
Install libprotobuf-dev as well
Print protoc version for debugging
apt-get update before installing protobuf
Attempt to fix websocket daemon issue through tomcat snapshot version
Gracefully allow clients to exit when the server-side closes the websocket

- Use tomcat snapshot version that fixes the issue with a lingering thread
- Use daemon thread for the heartbeat timer

Also fixed an issue where the session may have been closed by the time
the message handler is added by moving the code that add the handler
in Endpoint.onOpen implementation.
Update InstanceStats.java
Changed RestLogCallback listeners to a set to avoid registering the same
listener again.
Merge pull request #159 from nierajsingh/master

Changed RestLogCallback listeners to a set
Use File.pathSeparator instead of platform-specific "/" when building upload path.
Merge branch 'master' of https://github.com/davidstack/cf-java-client into davidstack-master
Merge branch 'davidstack-master'
Added checking for optional service plan fields before unboxing. Removed tests for optional service plan fields.
Updated link to Java client docs in README.
Merge pull request #168 from scottfrederick/docs

Updated link to Java client docs in README.
Merge pull request #166 from scottfrederick/win-upload

Use File.pathSeparator instead of platform-specific "/".
Merge pull request #167 from scottfrederick/service-plans

Added checking for optional service plan fields before unboxing.
Added script to install protobuf-compiler 2.5.0 on Linux machines.
Added build instructions to README. Changed install-protoc script to clean up after itself.