vcd_read: cleanup ifdefs

Clean up ifdefs so they make sense even if none or multiple are defined.

Also choose Linux as fallback case instead of failing, this
allows the code to compile e.g. on Android.

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@35971 b3059339-0415-0410-9bf9-f77b7e298cf2
http: fix for broken SHOUTcast streams

Support broken icy-metaint response from QuickTime Streaming Server.

The full version string is "QuickTime Streaming Server 6.1.0/532".
It sends a HTTP response header that contains an MP3 header!
Fixes bug #2133.

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@35987 b3059339-0415-0410-9bf9-f77b7e298cf2

Note that in mpv, "http://" is mapped to ffmpeg currently, and this
code is unused by default.
http: handle broken QuickTime Streaming Server headers

Handle the severely broken headers QuickTime Streaming Server sends.

Instead of ending the header with \r\n\r\n it ends with
\r\n<4 byte MP3 header>\r\n.
And programs like wget just silently accept this without even
printing a warning!!

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@35988 b3059339-0415-0410-9bf9-f77b7e298cf2

Note: see previous commit.
av_common: minor simplification
core: add --heartbeat-interval option

This closely follows MPlayer commit 36099, with some changes.

Move a mutable static variable into MPContext.
options: fix --no-colorkey

In the last cleanup round, this was accidentally changed from a store
option to int, and the option value was passed as flag value.

(Not that anyone needs/uses/cares about this option...)
demux_mkv: try to show current subtitle when seeking

Makes sure that seeking to a given time position shows the subtitle at
that position. This can fail if the subtitle packet is not close enough
to the seek target. Always enabled for hr-seeks, and can be manually
enabled for normal seeks with --mkv-subtitle-preroll.

This helps displaying subtitles correctly with ordered chapters. When
switching ordered chapter segments, a seek is performed. If the subtitle
is timed slightly before the start of the segment, it normally won't be
demuxed. This is a problem with all seeks, but in this case normal
playback is affected. Since switching segments always uses hr-seeks,
the code added by this commit is always active in this situation.

If no subtitles are selected or the subtitles come from an external
file, the demuxer should behave exactly as before this commit.