Add variable frontend/demux to tda_add
Add new tda_enabled flag and close frontend after getting information so other frontends can be proped
Add new dvb adapter enabled setting to extjs
make skip commercials an option in the webif (default to on)
dvr: added initial support for libavformat muxing
Adding sky UK mappings for NDS
Merge remote-tracking branch 'origin/pr/206'
[PR-206] dvb: extend the multi-frontend PR to include cleaner support.

Generally this is intended to be used such that a user can select which
frontend they wish to enable. However in theory with clever configuration,
configure one adapter then the other and enabling close fds and disabling
idle scan, it might be possible to use both frontends.

But since TVH doesn't do any form of arbitration strange errors might
occur if you try to access both frontends at the same time (which for
most such adapters is not possible).
Merge remote-tracking branch 'tvheadend/tvheadend/master'