-Added RegisterSingle method to IDependencyContainer
-Implemented RegisterSingle for SimpleContainer and SimpleInjectorContainer
-Renamed SimpleInjector container implementation as SimpleInjectorContainer to solve a namespace colition that will prevent the creation of a SimpleInjectorContainer instance.  The rename is also meat to prevent confusion, the name was being used for to different implementations.
Merge pull request #128 from caupolican/master

Added RegisterSingle method to IDependencyContainer