Geocoding - Revamp geocoder

[ericboucher]

Revamp geocoder to make code cleaner. Changes should include, at least:

• use of a base geocoding class
• clear differentiated geocoding and batch_geocoding functions
• standardized output in the event of an error

[tetraptych]

See also this library for standardizing geocoding requests.

[philipdickinson]

That looks dope.