Added section on running a developed extension
Added section on running a developed extension

Also some typos and updates.
jcass77/mopidy,ZenithDK/mopidy,jmarsik/mopidy,adamcik/mopidy,swak/mopidy,jodal/mopidy,bacontext/mopidy,priestd09/mopidy,quartz55/mopidy,jodal/mopidy,hkariti/mopidy,tkem/mopidy,ZenithDK/mopidy,hkariti/mopidy,tkem/mopidy,jcass77/mopidy,liamw9534/mopidy,dbrgn/mopidy,ali/mopidy,ZenithDK/mopidy,mokieyue/mopidy,tkem/mopidy,bencevans/mopidy,jmarsik/mopidy,glogiotatidis/mopidy,rawdlite/mopidy,SuperStarPL/mopidy,adamcik/mopidy,dbrgn/mopidy,bacontext/mopidy,bacontext/mopidy,kingosticks/mopidy,pacificIT/mopidy,ZenithDK/mopidy,tkem/mopidy,mopidy/mopidy,glogiotatidis/mopidy,vrs01/mopidy,bacontext/mopidy,jmarsik/mopidy,swak/mopidy,diandiankan/mopidy,bencevans/mopidy,bencevans/mopidy,mokieyue/mopidy,rawdlite/mopidy,mopidy/mopidy,dbrgn/mopidy,mokieyue/mopidy,jcass77/mopidy,dbrgn/mopidy,vrs01/mopidy,liamw9534/mopidy,adamcik/mopidy,woutervanwijk/mopidy,pacificIT/mopidy,ali/mopidy,priestd09/mopidy,hkariti/mopidy,glogiotatidis/mopidy,diandiankan/mopidy,mopidy/mopidy,SuperStarPL/mopidy,woutervanwijk/mopidy,vrs01/mopidy,kingosticks/mopidy,diandiankan/mopidy,quartz55/mopidy,jodal/mopidy,quartz55/mopidy,jmarsik/mopidy,pacificIT/mopidy,SuperStarPL/mopidy,quartz55/mopidy,ali/mopidy,bencevans/mopidy,rawdlite/mopidy,pacificIT/mopidy,glogiotatidis/mopidy,rawdlite/mopidy,hkariti/mopidy,priestd09/mopidy,vrs01/mopidy,ali/mopidy,diandiankan/mopidy,kingosticks/mopidy,mokieyue/mopidy,swak/mopidy,SuperStarPL/mopidy,swak/mopidy