Lots of changes (so I probably forgot some)

All components now take their owning entity during construction and attach to it.
Added a delegate class (that is unused at the moment)
Created a game interface class for the engine's use and extended the game class from it.
Renamed game class into ArtifactGame.
Added multiple new mesh generation functions.
All mesh generation functions now act on vertexdata instead of mesh components.
Changed how vertex attribute binding works to make it more flexible with regard to VBOs.
Added some convenience functions for sending VertexData to VBOs.
Fixed a const error with the CrossProduct function.
Deprecated system manager and moved its systems to be a direct part of the game; this gives the game class more control over when things happen and allows for each game to have its own copy of particular systems.
Added some new entities to better reflect what entities will be in the actual project.