Add a way to give feedback about the current CM

[maxplaga]

As far as I can tell after my first time of using the app there is no way to see the currently running CM identified so that could be a potential blocker for this proposal. But it would be nice to give feedback about the current mass.

Feedback Ideas:

• Speed (too fast / too slow?)
• Route (like / dislike)

This could become a part of the chat or be implemented in a new view. An alternative would be to just give feedback after the ride has ended.

[mltbnz]

I think that is a cool idea. We are partly joining the CycleHack this Weekend in Berlin and I will take the idea with me to discuss there.