Add feedback text to self assessments

Also includes fix to default text, and removal of a seemingly unused,
hardcoded 'estimated_time' context variable. A11y test uncommented.

JS got out of sync.

Add pylint and pep, with thresholds.

TNL-3742

Final Grade section in staff tools

TNL-3930, TNL-3761

Staff Assessment section in staff tools

Generalizing the display of completed assessments in staff tools, and
including staff assessments in the view, which had previously been missing.

Includes a new unit test for this behavior, and updates acceptance tests as well.

Version bump for staff grading

New i18n strings for release

Feature branch: ORA staff grading

ORA staff grading translation updates

Editor Assessments Order improvements

Now setting self.editor_assessments_order whenever we correct it for
template rendering, and modifying the logic to be more careful with
how assessments types not-specified-by-the-user are presented so
that they remain in the default, legal order.

Improve text strings

Changing wording of "waiting for peers" message.

Be robust to username not being available.

TNL-4019

TNL-4018

TNL-4027

These are the strings that were pulled from our source, pushed to
Transifex, and need to be pulled back down before merging all of
the staff grading work later this week.

Render Incomplete simplification

Simplfying logic for display strings in all "user action needed" states.

Fixing up oa_response

With staff now being a possibility, we need to update oa_response_complete.
Now keeping "Needs to be graded" and "You need to do things" separate. Includes
test fixes.

Staff can view uploaded files

Emulating the approach used by peer_mixin to allow staff to actually
see uploaded files. Also updates oa_student_info to make use of
oa_uploaded_file.html instead of duplicating that logic. Test
updates also included.

i18n fixes

Properly translate strings *before* passing as variable

Move focus within staff panels.

TNL-3932

Make checkboxes accessible.