perltodo: Add populating t/todo.t

Author: khwilliamson

Porting/todo.pod

@@ -38,6 +38,16 @@ Perl that s/he knows well enough to try to fix.  This task involves
 going through these bugs and assigning one or more labels, and removing the
 "Needs Triage" label if present.
 
+=head2 Transfer test failure cases to F<t/run/todo.t>
+
+We have more open bug reports than anyone can really grasp.  Most of
+those came with code to reproduce the failure.  We also have a test file,
+F<t/run/todo.t>, whose purpose is to hold these test failures.  This
+task is to add failing code to this test file, following the paradigm of
+those already in it.  It is likely that some of those bugs have already
+been fixed and nobody has realized it!  This is a gentle way to become
+familiar with perl's internals.
+
 =head2 Ongoing: investigate new bug reports
 
 When a bug report is filed, it would be very helpful to have someone do