Playlist item commands are soooo dirty :D

Some one with VC7 should test this commit

* Don't use the bandlimited resampler for downsampling (skew resampling for instance). The resampler doesn't have a low pass filter? This closes #256
 - on a side note, it also seems to fix the stack corruption (resulting in deadlock) issues i was having with audio output that was being resampled by auhal.

Add a test for pkg-config for ffmpeg. It now do in order: ffmpeg-config, pkg-config, default location, given tree. fixes #306. 
To cross-compile on a debian, use PKG_CONFIG_PATH=/usr/win32/lib/pkgconfig and --with-ffmpeg-config-path=somewhere with no ffmpeg-config (/usr/win32/bin by ex)

   vlc_next, vlc_previous, playlist_empty. Miscellaneous coding style fixes.

* playlist.m: fixed some "makes integer from pointer without a cast" warnings and moved "j" inside the #if 0 - block, so it isn't detected as "unused"
* wizard.m: run "resetWizard" when returning to the first page. Otherwise the encap-tab might not work properly (when switching from Streaming to Transcoding after having passed the streaming-method-tab)

Added new hotkeys (key-intf-hide, key-jump-3sec, key-jump+3sec, key-title-next, key-title-prev, key-chapter-next, key-chapter-prev) and expanded the hotkey structure. This is a forward port from branch vlc-0.8.1-jpsaman-thedj revision 11756.

* Fix some cosmetics

Track RTP sequence numbers and mark the first MPEG2-TS packet with a transport error when a discontinuity occurs.