Cache access to mpc-hc.ini (both read and write)
Make access to cached mpc-hc.ini thread-safe

Access to mpc-hc.ini cache map is now serialized.
A race was possible between filter graph thread and main thread, as
some internal filters use CWinApp::GetProfileX() functions to load its
settings.
Save mpc-hc.ini in UTF-8
Replace "On top > Never" by "On top > Default".

In most of the cases "On top > Default" will have the exact same behavior than "On top > Never" but it won't try to override the "on top" flag if an external tool sets it.

This commit fixes #2689.
Merge pull request #48 from alexmarsev/ini_cache

Cache access to the mpc-hc(64).ini for faster settings loading/saving.

Refs: #2837.
update ffmpeg (n0.8-19710-g35135a3)
Remove custom code needed in the past in order to successfully link ffmpeg library.
update h264_recov.c for the recent changes
Update our files for the recent FFmpeg changes.
H264 DXVA Decoder: Rewrote h264_dxva.c based on recent h264.c.
h264_dxva.c: update for the recent changes in ffmpeg
MPCVideoDec: Fix compilation.
update CFLAGS and ffmpeg/config.asm and ffmpeg/config.h
Fix DXVA after latest FFmpeg update.
update ffmpeg (n0.8-20314-g01a334e)