Clarifies what the roles are, makes Studio and LMS naming parallel.

[LMS-11372]
[LMS-11370]

This commit updates lms/templates.

These keys are now objects with a limited interface, and the particular
internal representation is managed by the data storage layer (the
modulestore).

For the LMS, there should be no outward-facing changes to the system.
The keys are, for now, a change to internal representation only. For
Studio, the new serialized form of the keys is used in urls, to allow
for further migration in the future.

Co-Author: Andy Armstrong <andya@edx.org>
Co-Author: Christina Roberts <christina@edx.org>
Co-Author: David Baumgold <db@edx.org>
Co-Author: Diana Huang <dkh@edx.org>
Co-Author: Don Mitchell <dmitchell@edx.org>
Co-Author: Julia Hansbrough <julia@edx.org>
Co-Author: Nimisha Asthagiri <nasthagiri@edx.org>
Co-Author: Sarina Canelake <sarina@edx.org>

[LMS-2370]

- Changed save OE message text
- Fix ICE legend positioning and content
- Add space to "offensive" checkbox
- Change tracker variable in undo to correct one

- Change wording when done with peer grading ("evals" -> "assessments")
- Added ICE legend item for comment syntax
- Added conditionals to display human readable 'grader_type' to alleviate confusion
- Rename 'Show/Hide Prompt' to 'Show/Hide Question'
- Reworded grading flags
- Make ICE grading container larger to more easily allow users to read and edit larger texts
- Adjusted lots of text and word choices to make them more user friendly
- Disable previous arrow on first grader feedback and next arrow on last grader feedback
- hide ORA instructions and ICE legend when calibrating so students don't feel like they need to write feedback

Changes after comments:

- Renamed instructions element and fixed casing issue
- Renamed legend class to ice-legend
- Changing condition from != to >= to not only fix incorrect one but also catch possible weirdness
- Grammar fix in a message
- Removing grader_type conditional in HTMl to give way to the one in python
- Moving ice feedback area height styling to CSS file

More changes:

- Update ICE version
- Modifying test to reflect code change
- Adding ICE undo feature

Squashed commits to facilitate cherry-picking.  Committers and
original commit messages are:
- ==> @caesar2164, * ==> @jrbl, ~ ==> @jbau

- Added boolean to OE problem CMS settings to turn on ICE track changes
- Added ICE init and tracking start/stop to HTML
- Conditional in Peer Grading HTML for ICE container
- CSS styling for ICE container and insertion/deletion elements
- Added class to track changes HTML
- Added ice.min.js as well as included it in the js requirements for peer grading
- Use track_changes in peer_grading_problem
* Refactor peer_grading_problem to lookup track_changes variable by problem location.
* Whitelist ICE insert, delete tags
* Adds ICE multi-user-editor insert and delete tags to the peer grading sanitize_html whitelist.
- add reset button

* Introduction ICE means we need its inline tags to get passed through
  to the feedback target, but we don't want malicious peer feedback
  providers introducing <script>, etc, so we use lxml.html.clean to
  scrub peer grading input.
* Adds feedback URL autoheating.
* Allows ICE <insert> and <delete> tags but not others.

~ add helptext re: EXPERIMENTAL FEATURES

~ address a bunch of @VikParuchuri review comments on ICE for OEE
  ~ remove extraneous code
  ~ change to new xmodule accessors
  ~ refactor filtering

~ fix broken test test_peer_grading_problem

~ Create track_changes.coffee and remove <script> from
  peer_grading_problem.html
~ Remove all reliance on id in favor of local scoping and classes

~ bring up test coverage somewhat

~ remove superflous $.scrollTo

~ TODO: Filtering

cleaned up padding for peer review training and grading states, removed extraneous response label,fixed style issue on rubric for peer grading where rubric items had a background color overridding the intended style

styling of peer review interface for students along with minimal adjustments to the staff grading interface as well. added internationalization of peer grading strings.

visual styling changes to staff grading and peer grading, along with additional instances of the use of the baseline variable instead of pixel definitions for padding and margins.

fixes template errors

keep tos untranslated

formatting fixes

has to have a certain naming structure

the 'closed' page a little nicer