plugin.cpp: on activation, set width and height in VLC configuration variables with plugin actual geometry, this prevents video rescaling when starting video

mkv.cpp: get ready to support pixel cropping (top/bottom/left/right) when it will work from the demuxer in VLC

* modules/video_output/x11/xcommon.c, modules/video_output/opengl.c, modules/video_filter/deinterlace.c: added on-the-fly cropping support to opengl and deinterlace.

--sout-udp-ttl takes precedence over -ttl

* src/video_output/vout_intf.c: added support for on-the-fly cropping in the core (needs some vout support).

  It's still not leak free. I suspect an error in src/misc/image.c

* modules/video_filter/deinterlace.c: fixed aspect-ratio + pass on cropping info (could be optimized to only deinterlace cropped part).

 * if --sout-rtp-ttl=0  use --ttl for c= line

different ttl each.
Need to re-think relations with --ttl and SAP within #404

In any case, that's ugly and thread-safe. The proper solution would
be to reimplement an atof() version that is locale-independant and
use in the many places that expect C/American float numbers. Even
then, there might be some buggy underlying libraries breakage
(e.g. Live555 ?).

Tested on Linux (both UTF-8 and Latin-x locales).
Needs testing on Win32.

I'm not explaining this again.

(fixes #406)

For absolute path use ftp://foo.bar//usr/local/etc/filename
-This line, and those below, will be ignored--

M    modules/access/ftp.c

(this command does nothing at the moment ;)

 * for RTP, prebuffering is done within RTP access
 * reordering now working within this buffer
 * solves synchro problems since packet rate is preserved