stream_bluray: remove unused variables

They were used for printing slave mode stuff, which was recently
removed.
manpage: fix vf_scale options
vf: print for which filter initialization failed
ao_null: fix unit mismatch with latency option

It's in seconds, but the code used it as sample count.
demux_lavf: one more hack for mp3 from network

mp3 has a hack lowering the probescore for format detection. This is
because detecting mp3s is hard due to their nature, and the fact that
ID3v2 tags are sometimes several megabytes big.

When playing mp3 from network, the mime-type is usually set, and that
matches the format hack entry meant for webradios, overriding the normal
mp3 entry. This can lead to network mp3s not being detected. Lower the
network case to the same probescore as on-disk mp3s. The difference is
that for network mp3s, we don't load the full probe-buffer, and we lower
the amount of audio the demuxer will read to collect data on opening
(0.5 seconds instead of typically 5 seconds).
audio: fix the exact value that is used for the wait time

The comment says that it wakes up the main thread if 50% has been
played, but in reality the value was 0.74/2 => 37.5%. Correct this. This
probably changes little, because it's a very fuzzy heuristic in the
first place.

Also move down the min_wait calculation to where it's actually used.
TOOLS/lua: no longer gsub out "lua/" prefix, now that its no longer there
TOOLS/lua/autocrop: handle case of user hitting hotkey while cropdetection already running
TOOLS/lua: use double quotes unless there's a good reason
options: let unknown option case be handled by final option parser

If an option is completely missing, let m_config_parse_option() handle
this case, instead of erroring out early.

Needed for the following commit.
options: print replacement for renamed/replaced options

Basically, extract the option table from DOCS/man/en/changes.rst, and
search the table if an option wasn't found. If there's an entry about
it, print it. Hopefully this behavior is slightly more userfriendly.

This is strictly bound to option names. It doesn't work for option
values, nor does it attempt to emulate the old option.
common: change mp_snprintf_append semantics

Make it more suitable for chaining. This means a function formatting a
value to a string using a static buffer can work exactly like
mp_snprintf_append itself.

Also rename it to mp_snprintf_cat, because that's shorter.
vo: get rid of config_count field

Doesn't really seem to be much of use. Get rid of the remaining uses of
it.

Concerning vo_opengl_old, it seems uninitGl() works fine even if called
before initialization.
vo: don't crash when changing panscan before first configuration

When the VO was not initialized with vo_reconfig(), or if the last
vo_reconfig() failed, changing panscan would cause a crash due to
vo_get_src_dst_rects() dereferencing vo->params (NULL if not
configured).

Just do nothing if that happens, as there is no video that could be
displayed anyway.
command: remove ifdefs for deint filters

Doesn't have much of a purpose.
vo: fix previous commit

Commit 433161 actually broke vo_opengl (and maybe others), because
config_ok is not necessarily set correctly yet _during_ reconfig. So a
vo_get_src_dst_rects() call during reconfig did nothing.
options: fix "-" (stdin) input

Input through stdin requires disabling the terminal layer, and commit
32c63f forgot to rename the option correctly.
TOOLS/lua: conform to whitespace coding-style
TOOLS/lua: add cycle-deinterlace-pullup script

Override the shift+d hotkey to add a pullup step to the cycle.
mixer: don't restore volume with different --softvol-max settings

Changing --softvol-max and then resuming would change the volume level
on resume to something different than the original volume. This is
because the user volume setting is always between 0-100, and 100
corresponds to --softvol-max gain.

Avoid that changing -softvol-max and resuming an older file could lead
to a too loud volume level by refusing to restore if --softvol-max
changed.