channel: fix channel_get_icon() - memory leak and handling
Partial revert "htsp: another fix for H264 - headers merge"

This reverts commit 33792bf6012c2913b346efa88c7a7c60116d4268.
H264: move avc parsing from globalheaders to mkv mux
avc parser: little optimization, pkt_meta is not used in avc_convert_pkt
DVR: improve the episode name saving, fixes #2357