MLP track detection is weak and will fail from time to time. If anyone
know a reliable way I am interested.
Only playing directly the AOB files is supported.

 There will be some regressions, I used automatic sed replacement with manual
checks but there was a lot to change.
 It's only the first pass.

This reverts commit 0bed6fc3.

It is broken (at least for ps).

This improves readability a lot and prevent us from reinventing the wheel.

Made demux2_IsPathExtension case insensitive.
Used demux2_IsPathExtension/p_demux->b_force when appropriate
Fixed a regression in flac demuxer (segfault when reading meta data)
Added a VLC_UNUSED(x) macro to avoid seeing ugly (void)x around the code.
Improved a bit a few vlc_common.h macro (do {} while(0))

   * the dts/ac3 changes fix some files from http://samples.mplayerhq.hu/evob/ and some other sources.
   * MLP doesn't have any know free decoder (nor do i have any sample) so this is basically "for the future"
   * VC1 doesn't work ... most likely needs some more changes to the code.
 * remove trailing spaces

* Headers in include must contain the structures and prototypes needed
  by the plugins and should be named vlc_*.
* Headers in include/vlc must contain the structures and prototypes
  needed by external libvlc clients

* Moved and renamed some things in headers. 
   - Removed vlc_cpu.h, vlc_error.h (merged in vlc_common)
   - Removed snapshot.h (merged in vlc_vout.h)
   - Removed vlc_spu.h (merged in vlc_osd.h)
   - Removed intf_eject.h and vlc_interaction.h (merged in vlc_interface)
   - Moved all internal headers to src
   - Merged vlc_video.h and video_output.h and move private things to src
   - Removed vlc/intf.h, vlc/aout.h, vlc/vout.h, vlc/decoder.h and vlc/input.h
     (meta headers for use in modules, and often implying too large 
     dependencies)
* Removed some useless dependencies
* Unexported a bunch of functions and structures used only in src/
  (--> Still some work here)
* Finally made input_thread_t and input_source_t (mostly) private. 
  Added input_GetItem to fetch the input_item of an input_thread
* Cleaned up deprecated entries in vlc_symbols.h and bumped up symbol 
  prefix

This commit has a 99% probability of breaking the build, 0.1% of killing
your cat and 0% of getting you hot chicks.

* when possible use the PTS for GET_TIME and GET_LENGTH. Note that this isn't always reliable. If you want you can disable it.

(da big courmischage)

* modules/demux/ps.c: improved MPEG PS autodetection a bit.

* include/vlc_es.h: added b_packetized field to es_format_t to tell a decoder if the input elementary stream will be fed in complete frames.
* include/vlc_codec.h: added a b_need_packetized field to decoder_t that is used by a decoder to tell if it wants to be fed complete frames.
* modules/demux/ts.c, modules/demux/ps.h, src/input/input_programs.c: b_packetized = VLC_FALSE.
* modules/codec/ffmpeg/ffmpeg.c, modules/codec/faad.c: b_need_packetized = VLC_TRUE;
* src/input/input_dec.c: if (b_need_packetized & !b_packetized) then kick off a packetizer that we'll use to feed the decoder.
* src/input/es_out.c: removed useless stuff.