- Added AbstractController that all controllers can extend.
- Modified Customers controller to work with AbstractController
- Added add/update support for CustomerAddresses
- Added delete support for CustomerAddresses but relevant fields in the db need to be created.
- When customer addresses is updated:
  - The country is checked for billing and shipping requirements,
  - The address is checked for validity
  - Other sanity checks are done

 - Added a client for the AVS service used by No more rack
- AVS checks for address insertion