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Git commits in Moodle 2.5.x by Jody Steele
commit 94b2dbb9b5e0da5efddf9eb496865d5fb2fe3d89 Author: Jody Steele <steelej@queensu.ca> Date: Wed, 16 Oct 2013 23:19:34 +0800 Tag: v2.5.3 MDL-38628 mod_assign: Allow a user to specify "No Grade" when grading an assignment submission