Split ffmpeg module in avcodec (decoders, encoders, deinterlacing), avformat (demuxers, muxers), swscale (scaling, chroma conversion) and postproc modules.

Do not use knowledge about the FFmpeg version in transcode.

With the mutex patch plus a few fixes.
Signed-off-by: Rémi Denis-Courmont <rdenis@simphalempin.com>

This could trigger some interface bugs, especially if they handle their callbacks carelessly. Revert if you have issues, but also consider to fix your interface.

libvlccore: "intf-show" is now a libvlc var instead of a playlist var. This removes a vout->playlist dependency.

Add ENABLE_NLS define, and make po files optional
Update source files to latest modifications
Add missing function checks
Define QT4LOCALEDIR
Require ncurses (I will submit a patch to cmake to check for ncursesw)

Note that an upper limit should be set anyway

This reverts commit e31c7798.

Damned, this is a hack to display psz_cat in the playlist.

So that vlc --{list,help,module} don't get us a non-null exit code

(cherry picked from commit a2d82490555eb3271a77b4958bc8528091951901)

Conflicts:

	modules/control/rc.c

/!\ In pure C, `()` means `(...)`, not `(void)`