JCLOUDS-782: init for shipyard provider

Initial commit for shipyard provider. My intent was to have the entire provider coded and in something like "good working shape" before I submitted a PR but @nacx strongly suggested I not do this.

This code base is a fork of the work @andreaturli is doing with docker so there may be more than a few similarities. Shipyard itself is essentially a docker manager allowing users to connect N number of engines (docker daemons) to a single source allowing you to work with them from a single location. A few points to note:

-There are literally no testers at this point. Working on this...
-Around 10 files or so are json that gets handed back from shipyard. Used for testing purposes and do not need to be looked over.
-The idea here is to implement the entirety of ComputeServiceAdapter. All methods except 'createNodeWithGroupIntoName' have been coded. Working on this...
-All 'listNodes*' methods are being ignored. Not entirely sure why...

shipyard API can be found here: http://shipyard-project.com/docs/api/

So with that said please take a peek and let me know what you think!
Same here. Is OkHttp mandatory for this provider? If not, just remove it and let users choose the HTTP driver.