* Avatar and Object now inherit from IEntity.
* Avatar.Position is now Avatar.WorldPosition to match IObject property.
* Implements event World.OnChat += delegate(IWorld sender, ChatEventArgs e);
* Adds IObject.WorldPosition and IObject.OffsetPosition - this is equivilent to AbsolutePosition and OffsetPosition in SOP respectively.
* Adds IObject.WorldRotation and IObject.OffsetRotation - as above.
* Renamed 'Material' to PhysicsMaterial (Wood, Glass, Metal, etc.). May want to place in subclass with other physics specific properties. (We however need to support these features in ODE/etc first.)
* Renamed Faces to Materials. IObjectFace to IObjectMaterial - this is for clarity for those coming from a 3D Programming background (it also makes more sense if/when we support Meshes in core). Properties and members remain identical.
* Added XMLDoc comments to IObject to assist people writing MRMs in XMLDoc aware editors.