By Denny Dyroff, Entertainment Editor, The Times RKCB Card players who specialize in bridge might get confused if they do a Google search and see that RKCB will be in Philadelphia on February 6. In their world, RKCB is a bridge play that means Roman Key Card Blackwood. Music fans, however, will not be confused when they see a listing for a concert by RKCB.    Send article as...