Update hash to discussion xblock
gradebook appears to bomb if there is no data to aggregate
Merge pull request #228 from edx-solutions/cdodge/gradebook-empty-protection

gradebook appears to bomb if there is no data to aggregate
Added new assistant role
Merge pull request #229 from edx-solutions/mjames/course_ta_role

Added new "assistant" role
ooyala/drag-n-drop: Update hash
Merge branch 'release' into master

Conflicts:
	requirements/edx/custom.txt