wined3d: OpengGL accelerated blits.

Implement some basic opengl accelerated blts from and to render
targets. It's not perfect yet, but enought to make some D3D apps
happy. For now the only supported operations are:

- Full screen back -> Front buffer: Just call present
- Offscreen surface -> render target
- Render target -> offscreen surface(slow)
- render target colorfill
3 files changed