Adds some use of submission deadlines to kick into over grading as needed.

Switch to using migrations

Prevent authors from submitting essays in Studio Preview mode

Revert management cmd

Avoid modifying an XBlock field (part 2)

Add fixtures for proofing the LMS

This reverts commit e0f5a8aa.

Conflicts:
	apps/openassessment/management/tests/test_create_oa_submission.py

Accept numeric xblock trace values

Avoid modifying rubric_criteria field

User innerHTML instead of innerText to support firefox

FIX - Re-clutter xBlock Workbench UI

Grade Status Template/Styling Work

There was a leftover TODO that needed to be fleshed out around the grading status. This will now list all the remaining steps when going through the assessment process.

Update management command test to fix test failure

Add management command for creating test submissions and assessments

Updating the grading section to display all the remaining steps

There was a leftover TODO that needed to be fleshed out around the grading status. This will now list all the remaining steps when going through the assessment process.

Fixing peer assessment for required grading of 1

Fixing a defect where the SQL query for getting a submission for peer assessment fails when the required number of assessments is set to 1. Updated a simple test to validate this as well.

Add in all the UI Workflow Hooks to have the correct front end behavior

Includes a number of JS changes, templates, and handlers to call the workflow api instead of complex, hard-coded logic.