t/run/todo.t: Add comments

Add a list of issues that we don't need TODO tests for, so that someone
doesn't waste their efforts.

Author: khwilliamson

t/run/todo.t

@@ -1,9 +1,16 @@
 #!./perl
 
-# This file is a place for tests that fail at the time they are added here.
+# This file is a place for tests that are failing at the time they are added
+# into this file.  It exists so that anyone can contribute a test without
+# having to know about Perl's testing structures.
 #
-# When a ticket is filed, just follow the paradigm(s) in this file to add a
-# test that shows the failure.
+# When a new ticket is filed, just follow the paradigm(s) in this file to add
+# a test that shows the failure.  However, some domains have infrastructure
+# which may make it easier to add a test there, than to have to set up things
+# here.  These include:
+#     Domain              Test File
+#   deparsing           lib/B/Deparse.t
+#   regex matching      t/re/re_tests
 #
 # It is expected that when new tickets are opened, some will actually be
 # duplicates of existing known bad behavior.  And since there are so many open
@@ -13,6 +20,41 @@
 # disposition of the test here determined at that time.  (For example, perhaps
 # it is redundant to the test demonstrating the bug that was intentionally
 # fixed, so can be removed altogether.)
+#
+# Before you add a test here, check that the ticket isn't one of these,
+# because we already have todo tests for them (in some other file).
+#
+# Git Hub issue numbers
+#     2207
+#     2208
+#     2286
+#     2931
+#     4125
+#     4261
+#     4370
+#     5959
+#     8267
+#     8945
+#     8952
+#     9010
+#     9406
+#    10750
+#    14052
+#    19370
+#    19661
+#    22547
+#
+# We keep a list of all the people who have contributed to the Perl 5 project.
+# If this is your first time contributing, you will need to add your name to
+# this list.  After you have changed this file with your new test, run
+#
+#   perl Porting/updateAUTHORS.pl
+#
+# This will automatically add you (if you weren't there already) to our list
+# of contributors.  You will need to commit this change by doing something
+# like:
+#
+#   commit -a -m'[your name here] is now a Perl 5 author'
 
 BEGIN {
     chdir 't' if -d 't';