Adds next/last refs #2632

Added the fact that since version 6.d, the `next` or `last` command in a loop that collects its last statement values
returns `Empty` for the iterations they run on.

doc/Language/control.pod6

@@ -1038,6 +1038,9 @@ while ($i < 10) {
 # OUTPUT: «1 is odd.␤3 is odd.␤5 is odd.␤7 is odd.␤9 is odd.␤»
 =end code
 
+*Since version 6.d, the C<next> command in a loop that collects its last statement values
+returns C<Empty> for the iterations they run on.*
+
 =head1 X<last|control flow, last>
 
 The C<last> command immediately exits the loop in question.
@@ -1073,6 +1076,9 @@ while ($i < 10) {
 # OUTPUT: «The last number was 5.␤»
 =end code
 
+*Since version 6.d, the C<last> command in a loop that collects its last statement values
+returns C<Empty> for the iterations they run on.*
+
 =head1 X<redo|control flow, redo>
 
 The C<redo> command restarts the loop block without evaluating the