* Added missing forward declarations.
* Added getters and setters to ShapeRendererOptions class.
* Cube primitive is indexed, modified the mesh creation accordingly. It
now uses MeshTools, link the library to DebugTools.
* Simplified resource handling so it's now handled in one place. It
still needs to be thought out better.
It was mainly in DimensionTraits usage. Also using DimensionTraits::*Type
for private members of physics shapes instead of manually specified
superclasses. The header is still included because of all the inline
accessors, so why not use the same type inside the class.