beatport: use new Distance objects (#302)
beatport: use new Distance objects (#302)

This also brought to light the fact that the distance calculations for tracks
was incorrect because there's no source field on TrackInfo objects yet. This
needs to be fixed.

ruippeixotog/beets,jackwilsdon/beets,parapente/beets,LordSputnik/beets,MyTunesFreeMusic/privacy-policy,kareemallen/beets,MyTunesFreeMusic/privacy-policy,PierreRust/beets,mried/beets,gabrielaraujof/beets,krig/beets,Dishwishy/beets,Kraymer/beets,untitaker/beets,madmouser1/beets,bj-yinyan/beets,jmwatte/beets,YetAnotherNerd/beets,Freso/beets,m-urban/beets,andremiller/beets,kelvinhammond/beets,kelvinhammond/beets,diego-plan9/beets,kelvinhammond/beets,mosesfistos1/beetbox,Andypsamp/CODjunit,kareemallen/beets,madmouser1/beets,swt30/beets,sampsyo/beets,xsteadfastx/beets,SusannaMaria/beets,sadatay/beets,ttsda/beets,multikatt/beets,tima/beets,andremiller/beets,lengtche/beets,tima/beets,imsparsh/beets,PierreRust/beets,drm00/beets,pkess/beets,dfc/beets,lightwang1/beets,drm00/beets,tima/beets,jackwilsdon/beets,artemutin/beets,mosesfistos1/beetbox,untitaker/beets,gabrielaraujof/beets,m-urban/beets,multikatt/beets,asteven/beets,Dishwishy/beets,shamangeorge/beets,pkess/beets,andremiller/beets,moodboom/beets,mathstuf/beets,marcuskrahl/beets,imsparsh/beets,sampsyo/beets,beetbox/beets,Kraymer/beets,jayme-github/beets,randybias/beets,kareemallen/beets,shamangeorge/beets,jmwatte/beets,xsteadfastx/beets,krig/beets,bj-yinyan/beets,moodboom/beets,LordSputnik/beets,Andypsamp/CODfinalJUNIT,jackwilsdon/beets,parapente/beets,moodboom/beets,swt30/beets,madmouser1/beets,arabenjamin/beets,mathstuf/beets,multikatt/beets,beetbox/beets,moodboom/beets,drm00/beets,shanemikel/beets,marcuskrahl/beets,mathstuf/beets,shanemikel/beets,ibmibmibm/beets,ttsda/beets,shamangeorge/beets,pkess/beets,ibmibmibm/beets,jcoady9/beets,Dishwishy/beets,Andypsamp/CODfinalJUNIT,jackwilsdon/beets,mathstuf/beets,shamangeorge/beets,Andypsamp/CODjunit,jcoady9/beets,ibmibmibm/beets,xsteadfastx/beets,Dishwishy/beets,asteven/beets,ibmibmibm/beets,mried/beets,diego-plan9/beets,sadatay/beets,mried/beets,lengtche/beets,ttsda/beets,PierreRust/beets,marcuskrahl/beets,LordSputnik/beets,Freso/beets,lightwang1/beets,YetAnotherNerd/beets,mosesfistos1/beetbox,kelvinhammond/beets,swt30/beets,tima/beets,dfc/beets,Andypsamp/CODfinalJUNIT,artemutin/beets,asteven/beets,jcoady9/beets,drm00/beets,Freso/beets,SusannaMaria/beets,Freso/beets,parapente/beets,Andypsamp/CODjunit,jmwatte/beets,ruippeixotog/beets,shanemikel/beets,randybias/beets,parapente/beets,randybias/beets,gabrielaraujof/beets,PierreRust/beets,Andypsamp/CODjunit,bj-yinyan/beets,jmwatte/beets,lengtche/beets,imsparsh/beets,sampsyo/beets,YetAnotherNerd/beets,Andypsamp/CODfinalJUNIT,ruippeixotog/beets,lightwang1/beets,Andypsamp/CODfinalJUNIT,dfc/beets,xsteadfastx/beets,swt30/beets,untitaker/beets,mosesfistos1/beetbox,m-urban/beets,Wen777/beets,sadatay/beets,bj-yinyan/beets,diego-plan9/beets,Kraymer/beets,beetbox/beets,Wen777/beets,sadatay/beets,YetAnotherNerd/beets,m-urban/beets,mried/beets,arabenjamin/beets,artemutin/beets,artemutin/beets,krig/beets,MyTunesFreeMusic/privacy-policy,diego-plan9/beets,madmouser1/beets,Wen777/beets,jcoady9/beets,SusannaMaria/beets,ruippeixotog/beets,lightwang1/beets,MyTunesFreeMusic/privacy-policy,asteven/beets,SusannaMaria/beets,shanemikel/beets,Andypsamp/CODjunit,marcuskrahl/beets,untitaker/beets,randybias/beets,arabenjamin/beets,imsparsh/beets,gabrielaraujof/beets,LordSputnik/beets,multikatt/beets,ttsda/beets,beetbox/beets,Kraymer/beets,pkess/beets,arabenjamin/beets,dfc/beets,lengtche/beets,sampsyo/beets,jayme-github/beets,kareemallen/beets