Added optional argument for play-plugin
Added optional argument for play-plugin

 * New config key "play -> optargs"
 * New Subcommand argument "-o", "--optargs"
 * Set position using "{}" within "play -> command"-string

MyTunesFreeMusic/privacy-policy,Kraymer/beets,mried/beets,diego-plan9/beets,kelvinhammond/beets,madmouser1/beets,lengtche/beets,shamangeorge/beets,arabenjamin/beets,swt30/beets,Freso/beets,Dishwishy/beets,LordSputnik/beets,Dishwishy/beets,tima/beets,asteven/beets,YetAnotherNerd/beets,mried/beets,diego-plan9/beets,xsteadfastx/beets,kareemallen/beets,shanemikel/beets,ibmibmibm/beets,m-urban/beets,gabrielaraujof/beets,YetAnotherNerd/beets,asteven/beets,ibmibmibm/beets,marcuskrahl/beets,kareemallen/beets,beetbox/beets,parapente/beets,jmwatte/beets,sadatay/beets,mosesfistos1/beetbox,lightwang1/beets,drm00/beets,kareemallen/beets,artemutin/beets,swt30/beets,SusannaMaria/beets,kelvinhammond/beets,madmouser1/beets,arabenjamin/beets,sampsyo/beets,Dishwishy/beets,m-urban/beets,tima/beets,randybias/beets,kelvinhammond/beets,jmwatte/beets,madmouser1/beets,asteven/beets,Kraymer/beets,marcuskrahl/beets,jmwatte/beets,MyTunesFreeMusic/privacy-policy,mosesfistos1/beetbox,drm00/beets,lengtche/beets,shanemikel/beets,madmouser1/beets,jcoady9/beets,drm00/beets,parapente/beets,tima/beets,MyTunesFreeMusic/privacy-policy,YetAnotherNerd/beets,ibmibmibm/beets,sampsyo/beets,pkess/beets,asteven/beets,shanemikel/beets,shamangeorge/beets,mosesfistos1/beetbox,Dishwishy/beets,sadatay/beets,LordSputnik/beets,gabrielaraujof/beets,lightwang1/beets,shamangeorge/beets,artemutin/beets,MyTunesFreeMusic/privacy-policy,xsteadfastx/beets,mried/beets,beetbox/beets,parapente/beets,pkess/beets,SusannaMaria/beets,pkess/beets,YetAnotherNerd/beets,arabenjamin/beets,beetbox/beets,randybias/beets,xsteadfastx/beets,jcoady9/beets,SusannaMaria/beets,parapente/beets,Freso/beets,m-urban/beets,kelvinhammond/beets,marcuskrahl/beets,jmwatte/beets,swt30/beets,drm00/beets,sadatay/beets,randybias/beets,diego-plan9/beets,mosesfistos1/beetbox,jackwilsdon/beets,shamangeorge/beets,jcoady9/beets,pkess/beets,gabrielaraujof/beets,artemutin/beets,gabrielaraujof/beets,mried/beets,randybias/beets,lightwang1/beets,SusannaMaria/beets,LordSputnik/beets,sampsyo/beets,artemutin/beets,beetbox/beets,lengtche/beets,kareemallen/beets,lightwang1/beets,jackwilsdon/beets,Kraymer/beets,lengtche/beets,jackwilsdon/beets,Kraymer/beets,tima/beets,m-urban/beets,ibmibmibm/beets,diego-plan9/beets,marcuskrahl/beets,shanemikel/beets,Freso/beets,sadatay/beets,jackwilsdon/beets,swt30/beets,xsteadfastx/beets,Freso/beets,sampsyo/beets,arabenjamin/beets,LordSputnik/beets,jcoady9/beets