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Git commits in Moodle 3.1.5 by Davo Smith
commit 0e69daef28417f3c1b5f1cedfef567c4f9642c69 Author: Davo Smith <git@davosmith.co.uk> Date: Tue, 24 Jan 2017 17:54:32 +0800 Tag: v3.1.5 MDL-57752 session: fix check_security() session termination