- stateblocks to IDirect3DStateBlockImpl interface and moving into
    a new file (stateblock.c)
  - shaders to IDirect3D*ShaderImpl interfaces
  - splitting vshader and vshader declaration as in dx9 into 2
    interfaces (for future common layer use)
  - vshader declaration code to a new file (vsaderdeclaration.c)
  - device calls to new interfaces (redirect stubs)
Simple texture fix for a little regression after last Jason's patches.
Some caps code using the GL/glext.h defines (GL_VERSION_*).