[Tachyon-14] TachyonURI (Client)

Internal methods that are deprecated should be removed as the refactor continues. Some questions left in the code as TODOs, will clean them up as they are addressed.
@calvinjia , @dcapwell means that instead of having a InetSocketAddress as a parameter of TachyonFS, it should have a TachyonURI as a parameter. 

Please create a sub JIRA to revisit this issue later.