(CCCP Patch) CCCP LAV Filters' defaults.

Enable the mixer for now, as Lord had problems with
the Windows one. Maybe with NT6 we'll all be able to
disable this without thinking too much about it :V

Also enable the LAV Splitter's tray icon for testing for now.
(CCCP Patch) Enable some additional things in ffmpeg

Also contains extra stuff to make both build scripts work locally
(CCCP Patch) Make LAV Video prefer YV12 to NV12 on XP
(CCCP Patch) Hack to make the tray icon be cleaned up better

Fixes crashes when used as "external internal" with MPC-HC when
the tray icon is enabled and the DShow filter chain is being
destroyed.