Agate requested to merge 689-mutations into develop Feb 18, 2019

This is a big MR, which implement all the backend/UI building blocks to deal with edits and edits suggestions.

Workflow for a regular user:

User notices a typo on a track title
User visit the track detail page and click the edit button
User suggest the correction
And admin (or anyone with the "library" permission) can review the change and accept/reject it
Once approved, the suggestion is applied

Workflow for an admin user (or anyone with the library permission):

User notices a typo on a track title
User visits the track detail page and click the edit button
User suggests the correction
The correction is applied immediatly, because the user has the required permission

All edits (approved and refused) are kept in the database for tracability.

Edits are supported for the following track fields: title, position (in album) and license. More field can easily be implemented. Support for edits on albums and artists should be pretty straightforward, but will be implemented in a separate MR.

This MR doesn't include any federation stuff, it will also be handled in a separate MR.