Renaming lat, lng to latitude, longitude

[nicho90]

to support spatial capabilities in Neo4j 3.x, using the point({latitude, longitude}) class as well as the built in function distance(point(a), point(b)): http://www.jexp.de/blog/html/full-text-and-spatial-search-in-neo4j-3.html

• Rename lat to latitude and lng to longitude in all apiControllers, controllers, templates and services
• Delete all lat and lng values in all indoor locations and introduce x, y values instead. This highlights the different reference systems of indoor & outdoor locations.