Consistently display the minimap button

## Use case

wanting to see the minimap when using transform tools

## Suggested solution

remove the "apply" button (virtually useless since #515 ) from all transform tool

### Possible drawbacks

- re-implement the minimap to have all the pixbufs on the preview
- auto-apply when saving

also:

- auto-cancel when "exiting" a transform tool with no modification

### Possible alternatives

none