signal discontinuities in the input
upipe_avfsink: fix use/release deadlock

upipe_avfsink wont release if muxer has not been
openeded or header has not been written successfully.
empty urefs list/release pipe in those cases to fix it.
pass incomplete pes to frames
helper_uref_stream: forward error and disc flags
avoid creating "holes" in TS unit tests
fix deadlock in a52 framer
bump up version to 0.4
player_chrome: add check for socket API
upipe-avfsink: remove timestamps offset for mpegts
documentation updates
Fix make check if missing ev.h
Merge pull request #5 from tmatth/master

Fix make check if missing ev.h
fix termination of workers
additional worker fixes
avcenc: set picture format