FOR-108

This will enable much cleanup of the relevant SASS rules.

The home button is removed, the search box is always displayed, and many
visual adjustments are made, along with a large amount of refactoring.

Originally reviewed in #4211

Thread entries now show an activity count that includes the original
post, and only one of the vote count and activity count is displayed
based on the user's selected sort. The sorting and filtering options now
both use a select and are somewhat more verbose, and the visual styling
of the sort/filter bar is updated.

Originally reviewed in #4165 with a bugfix in #4211

A thread will be labeled if it is pinned, if the user is following it,
or if it was authored by a staff member or community TA. This also
slightly changes the color used for community TA labels.

Originally reviewed in #4072

Use larger and lighter title font, decrease padding, and use lighter
solid backgrounds instead of gradients. Also, refactor SASS code to
conform better to our new style, including using more specific class
names.

Originally reviewed in #4072

FOR-545

Co-authored-by: Brian Talbot <btalbot@edx.org>

JIRA: FOR-591

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]

This removes the vote button from threads on the user profile, which was
the only interaction available on the page other than the link to view
the thread in the main discussion view.

JIRA: FOR-429

1. Add space between threads
2. Change Show/Hide to Expand/Collapse and visually separate it
3. Limit a thread to 700px high and scroll if longer

Co-authored-by: marco <marcotuts@gmail.com>

Students no longer see a tooltip nor any button affordance (i.e. cursor
and color change on hover/focus) on the pinning feature. For moderators,
the tooltip is now correct when a thread is pinned, the button is
accessible for keyboard-only users and screen readers, and an error
dialog now appears if an error occurs in attempting to pin/unpin.

JIRA: FOR-192

screen readers. Also, the mathjax message should be wrapped to prevent
non-IE browsers from complaining about a feature that is IE-only.

LMS-2156

Users will first be shown the first 25 responses of a viewed thread and
then have the option of loading 100 more at a time until all responses
have been loaded. This mitigates the performance impact of very large
threads by avoiding the need to render and transfer over the network
all content of a large thread at once. It will also allow students with
slower browsers to interact with large threads even if they cannot load
all of the responses.

- Clarify checkbox description wording
- Wrap checkbox and envelope icon in div to make it stand out
- Added styling for wrapper div
- Wrap label element around div to allow clicking the envelope to activate the checkbox
- Indented HTML and fixed if wrapping issue

JIRA: FOR-373

JIRA: FOR-400

JIRA: FOR-205

Also get rid of an unused template and extra copies of jquery.timeago.

JIRA: FOR-398, FOR-399

This change involves substantial refactoring of the relevant code to
reduce duplication. It also makes the templates for the vote buttons
more consistent and cleaner.

JIRA: FOR-64

A newer version was added to common/, so that is used instead. It is
also added to the set of JS files used in unit tests to allow forums
code in common/ to be tested.

This button has been broken for at least a year, so the code has
suffered from bit rot and should be reimplmemented if the feature is
necessary in the short term (which is unlikely since it has been broken
for so long).

The show/hide toggle now properly acts like a button, and focus is now
trapped on the loading element for both the show/hide action and loading
of a new page.