Support addressing by various global standards

[riordan]

We're primarily focused on letting people find places by how people refer to places; principally street addresses, areas, and points of interest. But there are other ways to place places.

These include:

• Latitude and Longitude
• Military Grid Reference System - which is being used for addresses in Dubai
• Google's Open Location Codes
• Geohash

When we detect one of these identifiers, we should be able to geocode to that region.

The wikipedia category on Geocoding Systems gives a pretty good overview, as does the comparison of systems done by open location codes.

Bonus Points

Reverse geocoding INTO these standards! You select a region, we'll give you the Open Location Code.