The XLib support has been dropped, so xcb and xcb-keysyms is now needed for
this plugin.

except those that have their own --enable-* switch.

It does not work very well but it need src/input and/or demuxer (mp3) improvments.

This gives metadata in WavPack files, for example.

This reverts commit 364868f9.
On deeper look, this deadlocks in all kind of places. I guess we'll
have to live with the racy Xlib behavior instead.

Conflicts:

	configure.ac

We need to call XInitThreads before anyone tries XOpenDisplay or
something, and XInitThreads itself is not re-entrant, so call it before
we start LibVLC. This only "fixes" Xlib with VLC. Other LibVLC users
need to do something similar themselves. LibVLC cannot do it. Other
application may have already connected to X before it starts LibVLC.

 * gather all tests (that I could find)
 * X_FLAGS -> X_CFLAGS
 * test for Xlib.h only once
 * cleanup defaults (especially XvMC was silly)
 * factorize CPPFLAGS

Qt: now that you don't control the controls size anymore, be careful to resize the controller when buttons show up.

Close #2487.

(see http://forum.videolan.org/viewtopic.php?f=2&t=56224&p=186350)

Those were never used from plugins. This commit is a no-brainer.

This could crash the input thread(s).

This allows invoking debuggers directly from the command line again!

This allows using the http interface directly when builddir != srcdir.
This is needed to get rid of the ./vlc script.

According to ffmpeg/libavcodec/mpeg12enc.c:155 (rev:2fd06be07311)
profile and level must be inited at the same time, so, -1 will be
returned for mp2v with width > 720 or height > 576. But, if we leave
this fields blank (i.e. FF_PROFILE_UNKNOWN and FF_LEVEL_UNKNOWN) avcodec
will init them correctly.

This partially reverts commit b1b72b63.
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>