Beta 6:

New vsync should finally work in all modes.

- Removed sound exclusive checkbox, WASAPI exclusive modes are now listed in select menu.
- New RTG vsync using low latency sync method, currently always triple buffered.
- Display selection GUI changed again, now lists both display adapter(s) and connected monitor(s).
- Associated ".uae" didn't set correct icon id (right click on .uae shows wrong or missing icon). Reset .uae association again to fix it.
- Fixed filter panel hang in some situations before emulation was started.
- Low latency vsync keeps list of modes that have already been calibrated, switching back to remembered mode uses stored calibration value.
- Unreliable old-style vsync options are gone. Replaced by low latency + double or triple buffered mode.
- DirectDraw low latency vsync fully implemented.
- RTG hardware cursor positioning fixed in aspect ratio corrected full window modes.