Finished Skin API except for NiSkinPartition.  Part of this was making NiSkinData read-only with a new interface.
Fixed a bug in the SubtractRef function.

Commented out functions written by Amorilia that I need to figure out how to fix.

Major update to python generation scripts and others.  Currently just namepace and mutable size members with appropriate generated code.

Made all include paths relative so you don't have to set any directories to compile.  Hopefully Amorilia will fix this in the code generation script.
Implemented a few more functions.