ScreenConstants.h merged with X3D_Utility.h
Moved component interfaces into an API folder with a distinction between external (end user's) and internal (X3D programmer's) APIs.
Updated drawing routines and TrigTables to use new path.
Ignore .a files in the source folder.
Moved clutter to a disable/ folder for now.
Fleshed out X3D_Math library a bit.