Introduce Str.comb(Int:D)
Introduce Str.comb(Int:D)

So instead of the slow (because using grammar engine) .comb(/../) you
can now do .comb(2), which is about 30x faster.

Gnouc/rakudo,jonathanstowe/rakudo,sjn/rakudo,nbrown/rakudo,ugexe/rakudo,raydiak/rakudo,rakudo/rakudo,ungrim97/rakudo,nbrown/rakudo,LLFourn/rakudo,rakudo/rakudo,sjn/rakudo,awwaiid/rakudo,ugexe/rakudo,MasterDuke17/rakudo,MasterDuke17/rakudo,samcv/rakudo,lucasbuchala/rakudo,jonathanstowe/rakudo,usev6/rakudo,ungrim97/rakudo,LLFourn/rakudo,sjn/rakudo,salortiz/rakudo,salortiz/rakudo,labster/rakudo,sjn/rakudo,Gnouc/rakudo,tbrowder/rakudo,ungrim97/rakudo,labster/rakudo,ungrim97/rakudo,MasterDuke17/rakudo,nbrown/rakudo,LLFourn/rakudo,ab5tract/rakudo,Gnouc/rakudo,raydiak/rakudo,b2gills/rakudo,tony-o/rakudo,dankogai/rakudo,lucasbuchala/rakudo,lucasbuchala/rakudo,azawawi/rakudo,paultcochrane/rakudo,jonathanstowe/rakudo,MasterDuke17/rakudo,dankogai/rakudo,ugexe/rakudo,tony-o/rakudo,azawawi/rakudo,ugexe/rakudo,labster/rakudo,labster/rakudo,Gnouc/rakudo,rakudo/rakudo,samcv/rakudo,tony-o/rakudo,b2gills/rakudo,softmoth/rakudo,awwaiid/rakudo,lucasbuchala/rakudo,azawawi/rakudo,azawawi/rakudo,salortiz/rakudo,rakudo/rakudo,ab5tract/rakudo,dankogai/rakudo,b2gills/rakudo,paultcochrane/rakudo,rakudo/rakudo,zostay/rakudo,Gnouc/rakudo,zostay/rakudo,tbrowder/rakudo,samcv/rakudo,tony-o/rakudo,jonathanstowe/rakudo,awwaiid/rakudo,raydiak/rakudo,labster/rakudo,zostay/rakudo,sjn/rakudo,usev6/rakudo,b2gills/rakudo,ugexe/rakudo,samcv/rakudo,dankogai/rakudo,softmoth/rakudo,tony-o/rakudo,LLFourn/rakudo,usev6/rakudo,lucasbuchala/rakudo,tony-o/rakudo,tbrowder/rakudo,jonathanstowe/rakudo,MasterDuke17/rakudo,LLFourn/rakudo,softmoth/rakudo,tbrowder/rakudo,dankogai/rakudo,usev6/rakudo,awwaiid/rakudo,zostay/rakudo,nbrown/rakudo,tbrowder/rakudo,salortiz/rakudo,ab5tract/rakudo,salortiz/rakudo,nbrown/rakudo,samcv/rakudo,MasterDuke17/rakudo,usev6/rakudo,raydiak/rakudo,Gnouc/rakudo,paultcochrane/rakudo,paultcochrane/rakudo,paultcochrane/rakudo,tbrowder/rakudo,nbrown/rakudo,softmoth/rakudo,rakudo/rakudo,azawawi/rakudo,ungrim97/rakudo,salortiz/rakudo,b2gills/rakudo,ab5tract/rakudo,labster/rakudo,awwaiid/rakudo,softmoth/rakudo,ab5tract/rakudo