Issue #196: Make use of Volley for Restful calls

* Make Movies retrieval use Volley for the RESTful calls.
* Add OkHTTP to use with Volley for caching and future SPDY support
* Refactor Subtitle code to use Volley
* Use StringBuilder in loops instead of string concat.
* Make use of SimpleXmlRequest for processing volley xml responses.
* Removes the old intent service and migrates it to use volley.  Also make
  sure to only get a single instance of a volley queue so that it is reused
  everytime.
* Refactor Episode Retrieval code
* Move Episode retrieval to volley