License metadata for every artefact

[Jiri Baum (Catalyst)]

Currently, adding license metadata to an artefact or page is achievable in an ad hoc fashion using a block on a page, but has many limitations.

It would be useful to add standard license metadata fields on every artefact and every artefact edit page. This would allow users to specify the license for the content they create or upload. To support content originating elsewhere, the users should also be able to enter the name of the licensor and original URL.

[Jiri Baum (Catalyst) (jiri-catalyst)]

Patches now on gerrit,
https://reviews.mahara.org/#/c/1930/
...
https://reviews.mahara.org/#/c/1939/

[Jiri Baum (Catalyst) (jiri-catalyst)]

For testing:

There are two site options under "General settings" where the feature can be turned on and custom licenses allowed/forbidden; a new admin page "Licenses"; institution settings whether licenses are mandatory and selecting the default license; and a user setting selecting the default license.