(libmpeg2/xvmc pending)

If too much frames have been dropped, then only decode I frames for a while and see if you can catch up with decoding other frames as well.

- ffmpeg-skip-frames    values: -1=None, 0=Default, 1=B-frames, 2=P-frames, 3=B+P frames, 4=all frames
- ffmpeg-skip-idct	values: -1=None, 0=Default, 1=B-frames, 2=P-frames, 3=B+P frames, 4=all frame)

That's very naughty.

audio: use avcodec_decode_audio2
       use block_Realloc to pad buffer.
	   fixed decoding when SplitBuffer is used (flac)

* 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.

  - Note that these are not all replaced atm, so some functionality might be lacking
* Make the minimum version of libavcodec version 5000 (september 2005).
  - Removed all the checks for previous API versions.

Also, make it clearer what is shared and instance-specific

So,
libvlc_t ==> libvlc_global_t
vlc_t ==> libvlc_int_t (internal instance)

p_object->p_libvlc ==> p_object->p_libvlc_globale
p_object->p_vlc ==> p_object->p_libvlc

VLC_OBJECT_VLC ==> VLC_OBJECT_LIBVLC

And by the way, there is some cleanup required :) (ie, some things are created in the global object instead of the instance-specific one)

* modules/codec/ffmpeg: try a bit harder to enable direct-rendering (some codec parameters are not yet set when opening the codec).

(da big courmischage)

 * modules/codec/ffmpeg/video.c: Better handling of aspect ratio change.

* modules/demux/mp4/mp4.c: we don't need to re-packetize h264 data into annexe B bytestream anymore since new versions of ffmpeg deal with it properly.

* modules/codec/ffmpeg/video.c: codec extra data is sometimes not available before the 1 frame is fed to the decoder.

* modules/codec/ffmpeg/*, modules/stream_out/switcher.c: fix compilation with new ffmpeg versions (use native timebase).

* modules/codec/ffmpeg: added support for Apple QuickDraw, QPEG, IBM Ultimotion, LOCO, Winnov WNV1, Autodesc RLE and Indeo V2 video codecs.

* modules/codec/ffmpeg/video.c: assume (M)JPEG YUV420 is the same as I420 (we could convert to have the exact chroma but that would be slower).

es_out.c: handle the pre-roll earlier

    - BLOCK_FLAG_CORRUPTED : signal corrupted data (do not use anymore
 BLOCK_FLAG_DISCONTINUITY in that case)
    - BLOCK_FLAG_PREROLL : mark this block to be decoded (no matter what).
 * ffmpeg, libmpeg2: support BLOCK_FLAG_PREROLL (ie disable frame dropping).
 * input: added ES_OUT_SET_NEXT_DISPLAY_TIME to ease the work for preroll
 (untested).
 * mp4: added support for CTTS table (pts, needed for h264+bframe).
 * decoders: for now handle discontinuity and corrupted block the same way.

* modules/codec/ffmpeg/video.c: libavcodec still doesn't handle avc1 properly so work around this until the issue is solved.