MainFrm: Prevent XySubFilter from being removed from the graph when cleaning up unconnected filters.

Temporary fix, either offer external subtitles as a pin on the graph or stop cleaning up the graph entirely.

Based on patch by Aleksoid.
Add AfxGetMainFrame() macro
PlayerSeekbar: code refactoring
PlayerSeekbar: smoother mouse seek
PlayerToolbar: be consistent with hand cursor

Previously it changed to arrow on right click
Update lcms2 to 8928bed.
Webserver: Convert the remaining png files to 8-bit.
Update docs/Compilation.txt for VS2012.
Updated Czech translation
Run astyle.
Update LAVFilters to 0.58.2
Update Changelog.txt and versions.txt
Updated German translation.
Updated Simplified Chinese translation.
About dialog: Add back the FFmpeg compiler in the clipboard output.
Improve the infinite recursion detection when parsing playlists.

The parser was sometimes too strict and rejected valid playlists.
Information bar: Show the chapter info when available.
Add some instructions about updating LAV Filters' submodule (draft).