Fix various sleep() issues
Fix various sleep() issues

- sleep(*) didn't work
- sleep-timer(Inf) returned immediately

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