[TACHYON-217] Add further documentation and unit tests

Initial attempt to add more documentation and tests for open delete and delete non-existing. These files make use of the eclipse formatting xml but used in IntelliJ hence some formatting differences may exist.
This is the result when I run the test. I get a ClientFileInfo object with all fields null and 0:

![debug](https://cloud.githubusercontent.com/assets/8416809/5026958/9f516604-6b21-11e4-8482-e0d18693443f.png)