docs: Add v2.0.0 release date
docs: Add v2.0.0 release date

ZenithDK/mopidy,kingosticks/mopidy,mopidy/mopidy,adamcik/mopidy,vrs01/mopidy,jodal/mopidy,jcass77/mopidy,adamcik/mopidy,ZenithDK/mopidy,ZenithDK/mopidy,vrs01/mopidy,mopidy/mopidy,jodal/mopidy,vrs01/mopidy,kingosticks/mopidy,vrs01/mopidy,jodal/mopidy,mopidy/mopidy,adamcik/mopidy,ZenithDK/mopidy,kingosticks/mopidy,jcass77/mopidy,jcass77/mopidy