Revision tool

This PR enables the replacement of our revision tool. It's now possible to

1. start the feedback from the drawing dialog
2. create a drawing from the feedback dialog

The user can then choose to attach the drawing as kml in the feedback dialg.

Please test here: [Test Link](http://mf-geoadmin3.dev.bgdi.ch/gjn_toggle_drawfeedback)

@p1d1d1 Maybe we can do a review session with Topo tomorrow, or next week.

@davidoesch Not sure about the texts of the buttons here and the UI in general (are buttons the right tool?)

@all Feedback welcome