added ILUT_VENDOR define, changed return type of ilutGetString to const ILstring
added ILUT_VENDOR define, changed return type of ilutGetString to const ILstring


DentonW/DevIL,Agadoul/DevIL,DentonW/DevIL,Agadoul/DevIL,DentonW/DevIL,Agadoul/DevIL,DentonW/DevIL,bcampbell/DevIL,bcampbell/DevIL,bcampbell/DevIL,Agadoul/DevIL,Agadoul/DevIL,Agadoul/DevIL,DentonW/DevIL,DentonW/DevIL,bcampbell/DevIL,bcampbell/DevIL,bcampbell/DevIL