Decouple "Route from/to here" and geocoder

[koebi]

We're currently experiencing a geocoder outage that results in the client being non-functional. While it is understandable, that it cannot search for places, it should still be able to use "Route from here" and "Route to here".

It seems that this is because every location gets reverse-geocoded before a route is being requested. This obviously fails, thus route generation fails. This should be decoupled in the sense that a routing request is still sent and the coordinates are used in the Start and End fields.