Make List.sum again 40% faster
Make List.sum again 40% faster

By skipping the special handling of the first element.  This also
reduces the bytecode size, but still too large to get inlined.  However
all of the method calls inside "sum" *are* inlined into "sum".

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