Adding branches to main library

After some deliberation, I have decided to fork simpleXrm.js into 3
separate libraries in order to keep the core library lightweight and
dedicated to fast and clean UI operations (show/hide, lock/unlock,
require/unrequire) on multiple fields.

The first new library is simpleXrmRest.js which adds OData REST Endpoint
operations (previously contained within the main library in the
simpleXrm.oData namespace). The second new library is simpleXrmLayout.js
which takes input arguments and produces layoutXml.