terminal output: if audio/video pts is missing, show "???"

Change the terminal status line to show "???" instead of a huge
negative number if audio or video pts is missing (there was a partial
workaround for audio before, but not video or A-V difference).
core: restructure main play loop, continue audio after video

Restructure parts of the code in the main play loop. The main
functionality difference is that if a video track ends first, now
audio will continue to be played until it ends too.

Now the process also wakes up less often if there's no need to update
video or audio. This will reduce unnecessary wakeups especially when
paused, but may make handling of input events laggier when fd-based
notifications are not supported (like most input on Windows).
mixer: reindent/cosmetic changes

There should be no real semantic changes.

Remove the mixer_setbothvolume macro, as it was unused.
options: move mixer.h options to struct
core: improve sub and audio start after timeline part switch

When switching to a timeline part from another file, decoders were
reinitialized after doing the demuxer-level seek. This is necessary
for audio because some decoders read from the demuxer stream during
initialization and the previous stream position before seek could have
been at EOF. However, this initialization sequence could lose first
subtitles or first part of audio.

The problem for subtitles was that the seek itself or audio
initialization could already have buffered subtitle packets from the
new position, and the way subtitles are reinitialized flushes packet
buffers. Thus early subtitles could be lost (even if they were demuxed
- unfortunately demuxers may not know about still active subtitles
earlier in the file, but that's another issue). Fix this by moving
subtitle and video reinitialization before the demuxer seek; they
don't have the problems which prevent that for audio.

Audio initialization can already decode and buffer some output.
However, the seek_reset() call done last would then throw away this
buffered output. Work around this by adding an extra flag to
seek_reset().
cosmetics: misc minor cleanups

The deleted ZRM* things were only relevant to vo_zr, which was deleted
earlier.
cosmetics: vf_vo.c: reformat
vo_xv: remove direct rendering support

Direct rendering support in vo_xv (used with --dr) had at least two
problems. First, OSD drawing modified the buffers; this meant that
if the buffers were used for reference frames there would be video
corruption. I don't think "performance optimization" with this level
of drawbacks is appropriate with today's machines any more. Direct
rendering could still be used for non-reference frames, but there's a
second problem: with direct rendering enabled the same buffer is used
for every frame, and with the XShm extension that is used by default
there's no checking that the previous frame has been completely
uploaded to the graphics card before it's overwritten by the next one.
This could be fixed, but as Xv is becoming obsolete I don't see it as
a priority to improve it. Thus I'm simply removing the parts of
functionality that were more likely to break things than improve
playback.
timeline: subs: keep subtitle tracks in source time

Timeline handling converted the pts values from demuxed subtitles to
timeline scale. Change the code to do most subtitle handling in
original subtitle source pts, and instead convert current playback
timeline pts to those units when deciding which subtitle to show.
The main functionality changes are that now demuxed subtitles which
overlap chapter boundaries are handled correctly (at least for libass
subtitles), and external subtitles are assumed to use same pts scale
as current source (this needs improvements later).

Before, a video subtitle that had a duration continuing past the end
of the chapter would continue to be shown for the original duration,
even if the chapter ended and playback switched to a position in the
source where the subtitle shouldn't exist. Now, the subtitle will
correctly end.

Before, external subtitle files were interpreted as specifying pts
values in timeline scale. Now, they're interpreted as specifying pts
values in source file time scale, for _every_ source file. This is
probably more likely to be what the user wants for the "main" source
file in case there is one, but almost certainly not quite right for
multiple source files where the same subs could be shown over
different scenes. If the user wants them to match some main source
file, it's probably still better to have incorrect extra subs for
video from some files than to have every subtitle appearing at the
wrong time. The new code makes it easier to change the interpretation
of the subtitle times, and some configurability should be added in
the future.
vo_gl: cocoa: add support for --ontop

Make the cocoa backend change the non-fullscreen window level
according to the value of the ontop property.
x11: fix setting UTF-8 window titles for some special cases

Setting the WM_NAME/WM_ICON_NAME window properties didn't always work:
apparently there are some characters that can't be represented in the X
STRING or COMPOUND_TEXT encodings, such as U+2013 EN DASH. The function
Xutf8TextListToTextProperty partially converts the string, and returns
a value different from 'Success'. This means vo_x11_set_property_string
didn't set these window properties.

On most modern window managers, this is not a problem, since these use
the _NET_WM_NAME/_NET_ICON_NAME and the UTF8_STRING encoding. Some older
WMs like IceWM don't read these, and the window title remains blank.

It's not clear what exactly we should do in this situation, but fix it
by setting set the WM_NAME/WM_ICON_NAME properties as UTF8_TEXT. This
violates the ICCCM, but at least IceWM seems to handle this well.

See also:
  http://lists.freedesktop.org/archives/xorg/2004-September/003391.html
  http://lists.freedesktop.org/archives/xorg/2004-September/003395.html
input: allow unicode keys and reassign internal key codes

This moves all key codes above the highest valid unicode code point
(which is 0x10FFFF). All key codes below MP_KEY_BASE now directly map
to unicode (KEY_ENTER is 13, carriage return). Configuration files
(input.conf) can contain unicode characters in UTF-8 to map non-ASCII
characters/keys.

This shouldn't change anything user visible, except that "direct key
codes" (as used in input.conf) will change their meaning.

Parts of the bstr functions taken from libavutil's GET_UTF8 and
slightly modified.
input: handle UTF-8 terminal input

This assumes the terminal uses UTF-8. If invalid UTF-8 is encountered (for
example because the terminal uses a legacy encoding), the code falls back
to the old method and feeds each byte as key code to the input code.

In theory, UTF-8 input could randomly fail, because the code in getch2.c
doesn't try to fill the input buffer correctly with input sequences
longer than a byte. This is a problem with the design of the existing
code.
x11: allow unicode input

This change allows using non-ASCII keys with X11. These keys were ingored
before.

Technically, this creates an invisible, non-interactive input method
context. If creation fails, the code falls back to the old method, which
allows a subset of ASCII only.
x11: add KP_Separator to key mapping

At least on some keyboards, the key between '0' and 'Enter' on the
key pad is mapped to KP_Separator. Since X11 VOs accept unicode
input, the mplayer keycode this key generates depended on the numlock
state, and with numlock enabled this mapped to an ASCII character.
This is probably not what the user wanted, since two physical keys
will always map to the same key code.

Map it to KP_DEC.
x11: input: add print and menu keys
x11: remove wskeys.h

Use the <X11/keysym.h> xlib header instead. I'm not sure why mplayer
defined these constants itself.
etc/input.conf: make file contents match default key bindings

There were some slight differences between what input.conf mapped, and
what was in input.c def_cmd_binds[]. Make them match.

Add some minor documentation improvements in input.cfg.

Also remove double comments ('##'), because they were confusing.
options, x11+cocoa: add option --cursor-autohide-delay

Add option --cursor-autohide-delay to control the number of milliseconds
with no user interaction before the mouse cursor is hidden.

There are two negative values with useful special meanings:
* A value of -1 prevents the cursor from hiding (useful for users
  with multiple displays).
* A value of -2 prevents the cursor from showing upon activity.

The default is 1 second to keep the behaviour consistent with the
past X11 backend implementation.

Remove the vo_mouse_autohide field as it was always true.
cocoa_common: accept window drag event from the whole window surface

Change the window to accept mouse drag events not only on the title
bar, but also on the rest of the window surface; this includes the
video area.

It looks like the changing of the window mask resets the behaviour
specified in the delegate method, probably due to some strange
interaction with NSBorderlessWindow. For this reason call
-setPresentationOptions in the -fullscreen method to remind cocoa the
behaviour we want.