Split Niflib and Niflib for Python into separate solution files to make explaining how to build them easier.

Implemented a missing Matrix44 function.
Updated ByteArray files to current generated versions.

Fixed double N's in NiTexturingProperty.

Made DLL creation optional and added a "Release - DLL" configuration.  The Release configuration creates a static library.

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.