* Example in region module:
Scene.GetModuleInterface<IMRMModule>.RegisterExtension<IMyInterface>(this);
* In the MRM:
//@DEPENDS:MyExtensionModule.dll
...
Host.Extensions<IMyInterface>.DoStuff();
* Interfaces now live in Interfaces subdirectory.
* Namespace does not yet reflect this change.
* Final namespace for MRMs will probably sit somewhere around OpenSim.Extend.MRM[?]