Refines general structure

JJ · JJ · commit bba739df251c · 2018-05-24T08:46:49.000+02:00
This (and the previous commits) refer to #114. This one takes a hint from https://perl6advent.wordpress.com/2009/12/07/day-7-looping-for-fun-and-profit/
diff --git a/doc/Language/iterating.pod6 b/doc/Language/iterating.pod6
@@ -8,11 +8,10 @@
 
 TBD
 
-=head1 How to iterate
+=head1 How to iterate: contextualizing and topic variables
 
 TBD
 
-TBD
 
 =end pod
 
