Copy over `group-of` helper from roast
Copy over `group-of` helper from roast

tony-o/rakudo,MasterDuke17/rakudo,Gnouc/rakudo,salortiz/rakudo,softmoth/rakudo,labster/rakudo,rakudo/rakudo,salortiz/rakudo,tbrowder/rakudo,rakudo/rakudo,MasterDuke17/rakudo,salortiz/rakudo,labster/rakudo,tbrowder/rakudo,nbrown/rakudo,MasterDuke17/rakudo,MasterDuke17/rakudo,salortiz/rakudo,Gnouc/rakudo,labster/rakudo,rakudo/rakudo,MasterDuke17/rakudo,tbrowder/rakudo,Gnouc/rakudo,Gnouc/rakudo,labster/rakudo,tbrowder/rakudo,tony-o/rakudo,tony-o/rakudo,tbrowder/rakudo,salortiz/rakudo,nbrown/rakudo,softmoth/rakudo,softmoth/rakudo,labster/rakudo,tony-o/rakudo,tony-o/rakudo,nbrown/rakudo,softmoth/rakudo,softmoth/rakudo,Gnouc/rakudo,rakudo/rakudo,labster/rakudo,rakudo/rakudo,nbrown/rakudo,tbrowder/rakudo,salortiz/rakudo,nbrown/rakudo,tony-o/rakudo,MasterDuke17/rakudo,nbrown/rakudo,Gnouc/rakudo,rakudo/rakudo