This is a squash of 38 commits ending with
5b080f979d692804452400ac5bed9b17c50b001e

- SOL-465: Initial implementation of certificates web view and signatories (names/titles)

- SOL-718 Close button is working properly

- SOL-801 Backbone Signatories Modeling

- SOL-803 Underscore template: Editor (Add)

- SOL-802 Signatories: Underscore template - Details

- SOL-804 Signatories: Underscore template: Editor (Edit)

- Add signatory delete Django view

- SOL-805 Signatory editor (Delete)

- Add Coffeescript router

- SOL-716 Jasmine Tests

- Added missing minified JS library

- client side validation of signatory fields

- SOL-390 signatories names

- Remove obsolete extends Sass files

- input maxlength limiting for signatory information

- SOL-389: Course title override

- SOL-466: Add capability to upload digitized signatures in Studio

- ziafazal: fixed css for upload signature image

- ziafazal: completed deletion of signature images

- UX-1741: Add initial static rendering/styling for Open edX web certs
  * creating new global static dir
  * adding static version of edX UX pattern library assets
  * adding web certificates static assets
  * adding static (+abstracted) web certificates rendering
  * creating two tiers of rendering (base + distinguished)
  * providing sample assets for certificate rendering
  * supporting RTL layouts
  * adding certifcates assests to edX static asset pipeline
  * temporarily hiding the mozilla open badges share action
  * wiring print button to print view/page
  * fixup! addressing conflict artifact in valid cert template
  * fixup! adding missing %hd-subsection sass extend + components comment clean up
  * fixup! correcting pattern library .hd-4 font-weight value

- SOL-468 Linked Student View for Web View Credential

- SOL-467: Add capability to upload organization logos for certificates

- SOL-391 / SOL-387: Signatory related info (assets) in certificates web view

- kelketek: Fixes for static asset collection in certificate HTML view.

- SOL-398 Web View: Public Access

- mattdrayer: Post-merge branch stabilization

- catong: Initial changes to Studio template and Help config file

- ziafazal: Branch stabilizations

- SOL-387: Display organization logo on LMS web view

- talbs/mattdrayer: Branch Stabilizations

- talbs: converting backpack action to use a button HTML element

- talbs: revising placeholder assets + their rendering in cert view

- mattdrayer: Username web view wireup

- SOL-386 Certificate Mode Previews

- SOL-905: Make organization logo and signatory signature uneditable

- SOL-922: Improve test coverage

- SOL-765: Add LinkedIn sharing

- [marco] temporary styling adjustment to account for smaller linkedin share image / fake button

- SOL-921: Address hardcoded template items

- SOL-927: Deleting certificate should delete org logo image also
  * updated invalid template
  * removed hr
  * fix invalid certificate error

- clrux: Add i18n to certificate templates and partials

- mattdrayer: Pylint violations

- SOL-920 Certificate Activation/Deactivation

- mattdrayer: Added LMS support

- SOL-932: Fix preview mode support in certificate view

- SOL-934: Fixed bug reported and broken tests

- SOL-935 removed the 'valid' word from web view title

- talbs: RTL support updates/fixes
  * revising certificate type icon/name vertical alignment
  * removing unused older certificate template
  * revising styling for message/banner actions
  * abstracting accomplishment type to use course mode + adding in honor/verified-specific placeholders

- mattdrayer: JSHint violations

Adds a new Email link to the instructor dashboard for frontend interface to send
email to course members. Adds a feature flag ENABLE_INSTRUCTOR_EMAIL to toggle this.
Creates a new djangoapp bulk_email that handles this action by getting the recipient
list and batching the emails to different celery tasks to do the actual sending.
Requires lynx package to convert HTML email to plaintext. Handles SMTP errors by
retrying or falling through to the next email. Adds the option to opt out of course
specific emails in the user dashboard with an Email Settings link for each course.
Uses severable configurable settings with defaults. DEFAULT_BULK_FROM_EMAIL
specifies the from address for email. EMAILS_PER_TASK specifies the number of emails
each celery task takes on. EMAIL_HOST, EMAIL_PORT, EMAIL_HOST_USER,
EMAIL_HOST_PASSWORD, and EMAIL_USE_TLS for the SMTP email backend settings.

Co-authored-by: Akshay Jagadeesh <akjags@gmail.com>

Embed a chat widget (much like the calculator widget) into the
courseware. To use, you must point it at an ejabberd box,
configured as `JABBER_DOMAIN` in the settings.

Just as is done with the main LMS application.scss file, rewrite the
course.scss file with Mako to conditionally import a theme's
variables overrides. Add the course.scss file to the list of ignored
Git files so that it doesn't keep getting committed over and over
again.

This also requires us to add a hardcoded line in the assets Rakefile
for the moment, so that the course.scss.mako file gets properly
preprocessed. Once the preprocessing is done by a Django management
command, we won't have to do this anymore.

This allows us to a) compile the coffeescript and sass from xmodules
using the new out-of-band method and b) reload xmodule static content
whenever it changes, which should make devs much happier.

The unused styles are referencing images that no longer exisit,
breaking collectstatic and therefore tests.

scss files that were still being partially used by the current
discussion forum.

This reverts commit 010bccc8.

This reverts commit 793354a0.