Ability to force an update

[mlablah]

As a user I would like to be able to trigger an update, despite there not being a newer version available.

Use cases:

• User messed with the addon files and want to restore them to mint condition
• Ajour has looked at the remote version and decided no update is available, but this might be due to obscure versioning

Proposed solution:
In the details view of an addon, add a "Force Update" button.
The button should only be available if Ajour has detected a remote version.
Clicking it should update the addon including its dependencies the same way a normal update is handled.