Removed the old SHAPE_ASSET macros
Implements AssetRef struct that acts as a universal wrapper for an templated AssetPtr and AssetId pair
Adds Type handling for AssetRef for ShapeAsset to unify handling in classes that utilize a shapeAsset, so assigning an assetPtr or an assetId will keep a record of the assignment in the event the assetPtr is invalid.
Update all classes that utilized the old SHAPE_ASSET macros to utilize the AssetRef struct and updated the class code to utilize it to provide much more clean and concise code that isn't blocked behind macro definitions
Added a new example class: shapeDatablockExample which allows render of a simple shape object utilizing a simple example datablock.
