Use a smarter semaphore in Supply.reduce
Use a smarter semaphore in Supply.reduce

Since the produced values can never be an nqp::null, use nqp::null as a
semaphore to indicate the first value has not yet been seen.  Removes the
need for a boolean semaphore.

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