the others as well), and call when needed as well.
- Change D3DFMT_R5G6B5 handling to make backdrop of Max Payne appear.
- Add code to reject attempts to use invalid texture units (Max Payne
  did this a lot).
- ValidateDevice fixme silenced as harmless but occurs frequently.
- Add trace which can be compiled in to debug vertex shaders, and
  correct fixmes and dprintf's into appropriate trace statements.
- Ensure we trace what we return when querying the device caps.
- Correct bug with negative numbers in vertex shader code.