build: remove leftover bits for internal libdvdread support

Support for internal libdvdread has been removed in commit 41fbcee1f55,
but some bits have been missed in Makefile/configure.

Support for libdvdread as normal library is left unchanged.
libmpdemux: remove demux_real, demux_viv, demux_audio

libavformat replaces demux_audio completely. I don't know/care what
vivo (demux_viv) is. libavformat has a Real demuxer; it seems it works
slightly better, with a different set of bugs.
Remove support for LIVE555 RTSP streaming

The main excuse for removing this is that LIVE555 deprecated the API
the mplayer implementation was using. The old API still seems to be
somewhat supported, but must be explicitly enabled at LIVE555
compilation, so mplayer won't always work on any user installation.

The implementation was also very messy, in C++, and FFmpeg support is
available as alternative.

Remove it completely.
Remove support for libnemesi RTSP streaming

Removed due to being a maintainance burden.
Support for FFmpeg is available.
Remove support for libdv

This removes the libdv demuxer and audio/video decoders. FFmpeg has
support for it, and it's even preferred over the internal decoders.
libmpcodecs: remove redundant audio and video decoders

Probably all of these are supported by libavcodec. Missing things can
be added back.

Also remove qtpalette.h. It was used by demux_mov.c, and should have
been deleted with commit 1fde09db6f4ce.
vd_ffmpeg, demux_mng: allow general raw formats, fix MNG demuxer

Change vd_ffmpeg such that if sh_video->format is a mplayer pixel
format, and there's no other codec information, try to play it as raw
video. (The case of no codec information happens if the "generic" ffmpeg
decoder is instantiated, which is tried last. This means clashes with
actual existing formats are less likely.)

demux_mng did not initialize all fields of the bih, which made vd_ffmpeg
do invalid memory accesses when trying to copy the extradata. Also, use
IMGFMT_RGB32 instead of creating the FourCC directly. (They should be
the same, but what if mplayer changes the IMGFMT_* values.)

This also fixes demux_rawvideo.
demux_gif: change format of packets to make it work again

The only decoder which could handle demux_gif's output was vd_raw,
which has been removed recently. Instead of re-adding vd_raw, make it
work with vd_ffmpeg.

By coincidence, the FourCC "raw " fits our needs and it understood by
the ffmpeg raw decoder (apparently used in mov files going by
libavcodec/rawdec.c). Since there doesn't seem to be any good way to
transport the palette in mplayer dmuxer packets, create an AVPacket for
this purpose. (struct sh_video provides a "global" palette. Rather than
hacking vd_ffmpeg to use it, it seems cleaner to make demux_gif use
AVPacket, which supports a per-frame palette.)
sub: remove unused definitions
osd: get rid of useless initialization function

The function merely printed redundant messages that were not visible by
default.
mplayer: fix command line arguments log output

In commit 94782e464d985b6e65, code was added to remove the first
command line argument. (Because that is essentially useless.) The code
for printing with command line on -v still assumed the first argument
should be skipped.
mplayer: enable talloc leak report if special environment is variable set

The functionality enabled with the --leak-report option is very useful
for debugging. Introduce a check for the MPLAYER_LEAK_REPORT environment
variable, and enable talloc leak report if it's set to "1".

The environment variable encourages enabling leak report permanently
during development. It's also a bit harder to get wrong: if the
--leak-report option is not the first option, it's silently ignored.
You can't put this option into a config file either. Enabling this
with --enable-debug in configure is not an option, because the leak
report code doesn't seem to be thread-safe, and thus is a bit dangerous.

Also, move the code to the very beginning to make sure leak report is
enabled before any other talloc function is used. Otherwise, these
allocations could be missed.
parser-cfg: specify which config file contains the unknown option

Also add some punctuation to the warning message.
manpage: document -use-filename-title removal/replacement