Developer credits
Git commits in Moodle 2.5.5 by Kevin Wiliarty
commit 5fe7d182d80ae81d10af100ae992c8c858d828ba Author: Kevin Wiliarty <kevin.wiliarty@gmail.com> Date: Wed, 21 Aug 2013 05:48:10 +0800 Tag: v2.5.5 MDL-39942: invite only users who can post to discuss