WL-926

2. Add site configuration overrides to theming/helpers.py
3. Move microsite.get_value from theming/helpers to site_configuration/helpers
4. Move microsite_configuration.microsite.get_value usages to site_configuration.helpers.values

Per Dave Ormsbee:
> That was from way back when, when we actually had Django server pools,
> proxied differently by nginx; one was the courseware, and the other
> was askbot, a discussion forum.
>
> They shared all the same code, but different parts were live. It was
> about as good an idea as it sounds.
>
> There is no reason that I can think of in the current day and age where
> you would ever want to run the LMS and *turn off courseware*.

TNL-3137

TNL-3137

TNL-3137

* Add action text to social media links.
* Make the alt text for mobile links more descriptive.

Serve branded footer JSON/HTML/CSS/JS from an API endpoint
in the branding app.  Refactor OpenEdX and EdX.org footer templates
to use the Python version of the API, ensuring that the API
values are consistent with the footer included in main.html.

Detailed changes:

* Added footer API end-point to the branding app.
* Footer API allows the language to be set with querystring parameters.
* Footer API allows showing/hiding of the OpenEdX logo using querystring parameters.
* Deprecate ENABLE_FOOTER_V3 in favor of the branding API configuration flag.
* Move no referrer script into main.html from the edx footer template.
* Rename rwd_header_footer.js to rwd_header.js
* Cache API responses.

Authors:
Awais Qureshi, Aamir Khan, Will Daly

Feature flagged. Puts a checkbox in the iframe. The iframe uses an organization_full_name parameter forwarded from Drupal by the courseware views and POSTs an email_opt_in parameter to the student views, preserving it on 403.

only redirect to dashboard if user has course enrollments, otherwise remain on the course catalog page (aka homepage or root)

update lettuce test to match new expected behavior

add Jason's feedback

only apply new redirect logic for microsites

switch to use a feature flag to determine whether to support redirect behavior

LMS-2719

Caution! This is backwards incompatible

catch additional FEATURE['ENABLE_MKTG_SITE'] checks and make sure MicrositeConfigurations will override the global setting

one more faulty login regarding ENABLE_MKTG_SITE=true situations

Introduction of the Microsite feature which allows for limited multi-tenant branding on a subdomain basis, e.g. foo.edx.org and bar.edx.org

fix errorenous logic when running a microsite that could reside in a hosting environment with a marketing site in front of it

pep8/pylint fixes

address PR feedback, remove underscore from test hostname

more pep8/pylint cleanup. Skip test_microsites test, it works on localdev, not on Jenkins. Need to talk with QA team

manually add Ned's single-to-double quote fix

change aws.py runtimes so that the microsite_dir that is read from configuration is changed to a python path

Conflicts:
	lms/templates/help_modal.html

LMS-1584