Add apartment field, with kinda-smart full address generation

If the user puts "123" in the apartment field, then the full address will
include "#123" after the street address.

If the user puts "Apartment 123", then the full address will have "Apartment
123" after the full address.

Fixes #63
Merge pull request #84 from jrunningen/master

Add apartment field, with kinda-smart full address generation