audio: Switch to decodebin2 in scanner and handle our own sources
audio: Switch to decodebin2 in scanner and handle our own sources

This is needed to be able to put in our own typefind and catch playlists before
they make it to the decoder.

pacificIT/mopidy,vrs01/mopidy,rawdlite/mopidy,ali/mopidy,jmarsik/mopidy,mopidy/mopidy,tkem/mopidy,tkem/mopidy,pacificIT/mopidy,bacontext/mopidy,glogiotatidis/mopidy,dbrgn/mopidy,kingosticks/mopidy,bencevans/mopidy,mokieyue/mopidy,rawdlite/mopidy,quartz55/mopidy,glogiotatidis/mopidy,diandiankan/mopidy,pacificIT/mopidy,dbrgn/mopidy,hkariti/mopidy,diandiankan/mopidy,bacontext/mopidy,jmarsik/mopidy,ZenithDK/mopidy,glogiotatidis/mopidy,diandiankan/mopidy,jcass77/mopidy,quartz55/mopidy,quartz55/mopidy,hkariti/mopidy,SuperStarPL/mopidy,kingosticks/mopidy,adamcik/mopidy,kingosticks/mopidy,SuperStarPL/mopidy,vrs01/mopidy,bacontext/mopidy,tkem/mopidy,jmarsik/mopidy,vrs01/mopidy,jmarsik/mopidy,jcass77/mopidy,swak/mopidy,swak/mopidy,jodal/mopidy,jodal/mopidy,mokieyue/mopidy,mokieyue/mopidy,swak/mopidy,bacontext/mopidy,SuperStarPL/mopidy,bencevans/mopidy,bencevans/mopidy,jodal/mopidy,glogiotatidis/mopidy,bencevans/mopidy,tkem/mopidy,ali/mopidy,dbrgn/mopidy,ZenithDK/mopidy,ali/mopidy,rawdlite/mopidy,dbrgn/mopidy,ZenithDK/mopidy,ZenithDK/mopidy,ali/mopidy,adamcik/mopidy,adamcik/mopidy,diandiankan/mopidy,swak/mopidy,quartz55/mopidy,mokieyue/mopidy,rawdlite/mopidy,hkariti/mopidy,mopidy/mopidy,mopidy/mopidy,hkariti/mopidy,jcass77/mopidy,pacificIT/mopidy,SuperStarPL/mopidy,vrs01/mopidy