Minimap V3

Steps before the release: 

- [x] Cleaning everything related to the previous DOM-based version
- [x] Proper Documentation of the new API
- [x] Port minimap events on the new `onDid/onWill` model.
- [x] Write tests for the new API so that we don't break things in the futur

@fundon, @jrouviere: If you see things that I missed for the release of a v3 please tell me.