Updating the Assessment Models
Updating over grading query to be more performant, and select a random submission
Merge pull request #228 from edx/sanchez/update_peer_workflow_timestamps

Updating the Assessment Models
Merge pull request #246 from edx/will/fix-due-date-text

Hide formatted due date in submission if it's not provided
Add missing view-level tests
Merge pull request #243 from edx/will/view-level-tests

Add missing view-level tests
Tag i18n strings in templates