add missing drag button -- see #676
add missing drag button -- see #676

walterbender/musicblocks,Hrishi1999/musicblocks,eohomegrownapps/musicblocks,Hrishi1999/musicblocks,Hrishi1999/musicblocks,eohomegrownapps/musicblocks,walterbender/musicblocks,walterbender/musicblocks,eohomegrownapps/musicblocks