Fix some issues with List.head/tail
Fix some issues with List.head/tail

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