Make IO::Spec::Win32.basename about 1.7x as fast
Make IO::Spec::Win32.basename about 1.7x as fast

- convert to native string in signature
- use nqp ops

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