Complex question type: License selector

[briri]

We need to define what we want the license selector to look like and its overall functionality.

Here is what it looks like in the current tool:

The system prefers the CC licenses by default. The template admin should be able to alter these defaults. When the user clicks on the 'Other licenses' link, it expands the list.

The list currently comes from SPDX

In the new system, we want to:

• Retain the default CC preferences
• Allow admins to modify those defaults for their template
• We have more info in the SPX metadata for these licenses. It would be nice to offer the description and perhaps the link so the user can go read the license definition. For example: https://spdx.org/licenses/CC0-1.0.html

See corresponding infrastructure ticket for managing the SPDX dataset