routing: GraphHopper interface change for allowing viapoints

Change routing query and interface with GraphHopper service for
adding viapoints support.
Remove query properties to and from and add a new property viapoints
that is a coordinates array.
A query is legal if there are at least two viapoints.

https://bugzilla.gnome.org/show_bug.cgi?id=731068
Others
WIP! Initial routing sidebar code.
More sidebar work
more sidebar work
more sidebar work

Conflicts:
	src/mapLocation.js
	src/routeQuery.js
	src/routeService.js

Conflicts:
	src/routeQuery.js
	src/routeService.js