Add test for track.last_modified = 0
Add test for track.last_modified = 0

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