API endpoint for licenses

[lenasterg]

Problem

Currently, there is no Openverse API endpoint for the available/deprecated licenses.

Description

An API endpoint for the licenses which it could contain for each license also info data ex:

• shortname ex: BY-SA
• Full name ex: Attribution-ShareAlike 4.0 International
• icon url: ex: The black color icon URL
• description: A short description
• Use: ex: Commercially or Not
• more info url: The URL of the license info ex: https://creativecommons.org/licenses/by-sa/

Ideally, there should be language-based endpoints URL so the above info can be changed by the localization teams.

[krysal]

Related to #63.