Cleanup XBMCAddon::xbmcgui::Control class

The codegenerator now handles dynamic typing (that SWIG alone could never do) by using RTTI on the objects passed so that their concrete types, rather than their current static types, are considered correctly when being returned to python. This allows us to remove a lot of extraneous virtual methods from the Control parent class.

Removed all of the extraneous methods of the parent Control class.

Added more documentation and removed some things that were only visible for reasons no longer viable.

Hide show/close from python in WindowDialog since they are inherited from Window.

Also added a simplistic hack for handling dynamically typed parameters to methods using an Alternative<T1,T2> template. The only better step would be full support of overridden methods. This allows the removal all of the explicit python code in the *.i files (with the exception of the rich compare _rcmp on the Action class).