1. add new api calls to 1. set a "native surface" for image objects. this

1. add new api calls to 1. set a "native surface" for image objects. this
currently does nothing and i have kept it VEEERY generic it's a pointer to a
native surface which can be just about anything - each engine will probably
define a format of its own you need to use VIA the native surface type.
2. add calls to set/get colorspace - moving this down into the engine level.
so far engines do nothing at all with it - but api is there.
3. clean up gl engine a bit - make it more standard.

SVN revision: 27389