Disable randomized-problem test until bug-fix is merged in.
reenable psychometrics for regrading
Change updating of CourseTaskLog to mostly occur in worker thread.
Rename fields in CourseTaskLog, including a task_key column for indexing.  Use 'rescore' instead of 'regrade'.  Clean up task submission.
Rename task_queue.py to task_submit.py.
Add dogstat logging to background tasks.
Move code to instructor_task Django app.
move test_tasks to test_integration.
set task_id on LMS side.
tasks now extract task_input and course_id from InstructorTask, instead of passing explicitly.
factor out InstructorTaskTestCase base class, for reuse in test_tasks.
initial test_tasks
Fix progress reporting.
Handle failure task_output that won't fit in the model column.
Fix issue with unicode in errors.
Refactor test_views from test_api.  Pull out pending_tasks.js.
Added deletion tests
Removed unused test code
Rename system_test to get_test_system
Merge branch 'master' into jonahstanley/add-gradingsettings-tests