fix missing inline keyword
remove upipe_xfer_mgr_detach
add opaque and uchain to upump manager
fix bogus sync header changes
fix bogus discontinuities
also set systime
misc adjustments
fix octetrate and vbv buffer
init opaque and uchain in upump manager
make qsink accept a pseudo-output
add vbv buffer size to flow def
fix next_pts_sys
new urefcount_dead function
add opaque to struct upipe

Also add upipe_sub_get_super(), and move sub_mgr to upipe_get_sub_mgr().
Also add flow_id in flow definitions.