libav: fixed compiling issues with more recent versions of libavcodec
Only compare the serieslink field when comparing an event with a serieslink auto recording.  Previously tvh was also comparing other fields, including title, which broke some serieslink recordings (e.g. if the episodes had unique titles).  Fix by adamsutton.
Description tag fix
Merge pull request #281 from petriposio/issue/1689

Description tag fix
Merge https://github.com/tvheadend/tvheadend