Clicking on conflicting option box unchecks all conflicts
LMS: Clicking license text should bring to new window
updated styles to reflect html reuse inside of xblock edit modal area.

Add ARIA attributes to license for a11y

Gracefully handle re-selecting of selected license

Use native checkboxes for courseware license options
In Studio settings editor for video module, don't show license if feature-flagged off
Don't let Scope.contents fields leak to Studio editor
JS gettext() must all be on the same line for i18n
Add docstrings for bok-choy tests
Remove LicenseMixin from HTMLDescriptor
Responding to UX review feedback
Add aria-pressed attribute
Use https links instead of protocol-relative links for links to creativecommons.org
Remove license from course outline page in Studio

This allows course authors to choose between two difference licenses for their
course content: All Rights Reserved, or Creative Commons. In the backend, XBlocks
that wish to allow custom licenses need only inherit from LicenseMixin, which
adds a `license` field as a string.

License information is displayed in the Studio editor view, and just below the
rendered XBlock in the LMS. In addition, if the course block itself has a custom
license set, this license will display just below the main body of the page
on courseware pages.

This entire feature is gated behind the LICENSING feature flag.