Add in-app map!

Summary: Add in-app map accessible from the button on the top menu. Change function to view a fovourite stop on the map.

Reviewers: Libre BusTO , valerio.bozzolan, fabio.mazza

Reviewed By: Libre BusTO , valerio.bozzolan, fabio.mazza

Subscribers: valerio.bozzolan, fabio.mazza

Tags: Libre BusTO

Maniphest Tasks: T15

Differential Revision: https://gitpull.it/D24