This applies the "whitelist" => "include" changes to all the core
phpunit_coverage_info occurrences, so core won't emit any deprecation
warning (see previous commit).
At the same time, modified a bunch of comments in coverage files
to be more readable/understandable.
This patch adds new capabilities:
'mod/forum:postprivatereply' - whether a user is able to post private replies; and
'mod/forum:readprivatereplies' - whether a user is able to read private replies.
Private replies are only visible to the intended recipient (the author of
the parent post), the author of the private reply, and those with the
ability to read private replies.
If a post is private then it cannot be replied to further.
Eloy Lafuente (stronk7)