widechar classes.
- fix a stupid bug in callback handling caught by Lionel.
- add some forgotten IID on class factory (better if we want to active
the code)
- many cleanups on COM Macros (don't need A and W variants as they are
the same)
Implemented circular buffering for the dinput mouse device.
Mapped the mouse warp on the center of the cooperative window, which
should make windowed games work better in managed mode.
