Add PlaceFormatter class

The purpose of this class is to get the relevant GeocodePlace properties
for the available place types. The class is implemented to be UI
agnostic, so it can be reused in many parts of Maps.

https://bugzilla.gnome.org/show_bug.cgi?id=726625
searchResultBubble: Use PlaceFormatter class

https://bugzilla.gnome.org/show_bug.cgi?id=726625
Add wrapper module for the Overpass API

Overpass QL: http://wiki.openstreetmap.org/wiki/Overpass_API/Overpass_QL

https://bugzilla.gnome.org/show_bug.cgi?id=726625
placeStore: Make exists method public

https://bugzilla.gnome.org/show_bug.cgi?id=726625
placeStore: Add get method

https://bugzilla.gnome.org/show_bug.cgi?id=726625
Use Overpass to get extra info for search bubble

https://bugzilla.gnome.org/show_bug.cgi?id=726625
Place: Add wheelchair translations

https://bugzilla.gnome.org/show_bug.cgi?id=726625