s/continent_code/code/g
Remove some repeated code for defining traits for each record
Fix City & CityISPOrg - both needed the Role::HasSubdivisions role

Also added tests for these classes.
Actually add the test files for City & CityISPOrg
Add MaxMind record class

Refactor test code to share tests in a library
Add Postal record class and remove postal info from Location
Add docs to the Model classes for the new maxmind and postal methods
More changes for next release
Tidy code
Fix some doc bugs for the MaxMind record class