Git commits in Moodle 3.3.3 by Connor Sheremeta

commit 2479e3742b273a9a1463c7fb54e6c0afedef6d47
Author: Connor Sheremeta <sheremet@ualberta.ca>
Date:   Wed, 30 Aug 2017 03:31:18 +0800
Tag:    v3.3.3

MDL-54540 lti: Add allowfullscreen attribute to LTI IFrames