It allows to:
 - properly support filters that do not have 1:1 input/output relation
 (yadif2x, bob, ... are back).
 - filter only once each picture (for the 'static' filter chain). It
 fixes filters with state behavior.
 - display as soon as possible the first frame after a flush.

There are still a few issues:
 - when paused, on filter changes, the picture displayed step forward the
 first time.
 - preventive frame dropping is not enough agressive.

 Due to the way dynamic configuration is managed, the static chain contains
only deinterlace/postproc for now.

As reported by xxcv

Close #3996

Should fix #4078 , same issue was in linux side also.

 I am not sure it had consequences, but it seems more logical and
it follows the libxml2 code example I found (reader1.c).

 xml_ReaderReset(reader, NULL) followed by xml_ReaderDelete(reader) lead
to a double free.
 xml_ReaderReset(reader, stream) would leak the module upon error.

The script is faster and decrease the load on the server.

Close #4041

Our NEON optimizations don't compile on ARMv5 and lower. It is
dubious that there would be any use for NEON on such processor anyway.

See http://forum.videolan.org/viewtopic.php?f=2&t=81103
http://forum.videolan.org/viewtopic.php?f=14&t=80008
http://forum.videolan.org/viewtopic.php?f=13&t=73500

You know, there is a wiki that is actually useful

This fixes a compil problem on FreeBSD

pointed out by jsa@FreeBSD.org

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>