Adds Sphinx Documentation

* Adds documentation for Client and managers. The CLI code isn't covered yet.
* Consolidated iter logic into Client.call instead of Client.__call__. It's much easier to document that way.
* Added iter_call to SoftLayer.Service
* Added some missing doc blocks and fixed some incorrectly formatted blocks.
* Adds fabric script to build docs and push them up to github via gh-pages. Viewable here: http://softlayer.github.com/softlayer-api-python-client.