Add Creative Commons 4.0 as licence types to the admin-controlled licenses

[Kristina Hoeppner]

Similar to bug #1265982, the default CC licenses that Mahara ships with that a site admin can control under Administration -> Config site -> Licenses need to be updated to CC 4.0. Existing sites need to be able to continue working with CC 3.0, but new sites should only see 4.0 as options.

Thus, an existing site will have all CC 3.0 licenses and 4.0 licenses displayed in the list of licenses. It's then up to the admin to decide whether to delete any of these.

[Jono M (jonom)]

https://reviews.mahara.org/#/c/2963/

[Jono M (jonom)]

Fixed in the above patch along with Bug #1265982