Creative Commons Licensing for edX

This PR adds Creative Commons Licensing to the Open edX Platform.

Review tickets
T&L https://openedx.atlassian.net/browse/TNL-195
UX https://openedx.atlassian.net/browse/UX-948
Your indentation is weird. It doesn't like that `switch` is an inherently confusing construct -- I'd suggest that you use `if`/`else` instead.