Make SetHash.grabpairs(N) about 3.5x faster
Make SetHash.grabpairs(N) about 3.5x faster

- using the same logic as SetHash.grab(N)
- except for returning a Pair with the object instead of object itself

nbrown/rakudo,sjn/rakudo,softmoth/rakudo,softmoth/rakudo,tony-o/rakudo,labster/rakudo,usev6/rakudo,awwaiid/rakudo,rakudo/rakudo,salortiz/rakudo,nbrown/rakudo,awwaiid/rakudo,raydiak/rakudo,Gnouc/rakudo,Gnouc/rakudo,tbrowder/rakudo,salortiz/rakudo,MasterDuke17/rakudo,tbrowder/rakudo,tbrowder/rakudo,sjn/rakudo,awwaiid/rakudo,nbrown/rakudo,MasterDuke17/rakudo,tony-o/rakudo,sjn/rakudo,tbrowder/rakudo,tony-o/rakudo,rakudo/rakudo,labster/rakudo,salortiz/rakudo,labster/rakudo,rakudo/rakudo,usev6/rakudo,raydiak/rakudo,awwaiid/rakudo,jonathanstowe/rakudo,awwaiid/rakudo,salortiz/rakudo,lucasbuchala/rakudo,tony-o/rakudo,usev6/rakudo,jonathanstowe/rakudo,salortiz/rakudo,usev6/rakudo,rakudo/rakudo,MasterDuke17/rakudo,jonathanstowe/rakudo,salortiz/rakudo,Gnouc/rakudo,rakudo/rakudo,Gnouc/rakudo,tbrowder/rakudo,Gnouc/rakudo,raydiak/rakudo,lucasbuchala/rakudo,jonathanstowe/rakudo,labster/rakudo,lucasbuchala/rakudo,MasterDuke17/rakudo,tbrowder/rakudo,sjn/rakudo,raydiak/rakudo,Gnouc/rakudo,lucasbuchala/rakudo,softmoth/rakudo,sjn/rakudo,labster/rakudo,tony-o/rakudo,nbrown/rakudo,usev6/rakudo,labster/rakudo,jonathanstowe/rakudo,MasterDuke17/rakudo,softmoth/rakudo,nbrown/rakudo,rakudo/rakudo,tony-o/rakudo,MasterDuke17/rakudo,lucasbuchala/rakudo,softmoth/rakudo,nbrown/rakudo