This was forgotten when the parser for mplayer2 EDL files was removed.
Change the header of the mpv EDL format to include a '#', so a naive
parser could skip the header as comment. (Maybe this is questionable;
on the other hand, if it can be simpler, why not.)
Also, strip the header in demux_edl.c before passing on the data, so the
header check doesn't need to be duplicated in tl_mpv_edl.c.
Edit Decision Lists (EDL) allow combining parts from multiple source
files into one virtual file. MPlayer had an EDL format (which sucked),
which mplayer2 tried to improve with its own format (which sucked). As
logic demands, mpv introduces its very own format (which sucks).
The new format should actually be much simpler and easier to use, and
its implementation is simpler and smaller too.
mpv crashed when linked files were not found. The reason was that the
chapters array contained some uninitialized data.
I have no idea how this code works (after the merge). The old code
actually seems to remove missing chapters, while the new code just
leaves them unintiialized. Work around the crash by initializing the
chapters array (and a bunch of other things) with 0, which means the
missing chapter will be located at 00:00:00 and have no name.
There is a regression since commit af0306d.
All these files access mp_core.h and MPContext, and form the actual
player application. They should be all in one place, and separate
from the other sources that are mere utility helpers.
Preparation for splitting mplayer.c into multiple smaller parts.