Make sure factory-generated assignments are created open
Make db:populate generate assignments of variable due_time
Test for submissions only createable on open assignments
Check for assignments being open before creating a submission
Add sign_out utility method for tests
Test for verifying course membership and signin for submission creation
Check signed in and enrolled in course for submissions
Test for current_user? with call to current_user, not reference to @current_user

Damn that's a subtle bug.
Add tests for an option to delete courses
Add a helper for links with icons prepended
Add delete and edit links, now with icons
Add a destroy action on courses