Implemented Idea 2 from #1532
Implemented Idea 2 from #1532

 * New argument `--optargs` reads string from option
 * If "{}" is present in the given string, the `optargs`
   from config-file get inserted at that point.

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