Add addresses to organizations

[duytsev]

Implements a feature: Add address to an organisation.

Assumptions and ideas:

• I decided to keep country_code in organization while address has a city_id reference which is also derived from country_code + city_name. I assumed that org country and address country could be different.
• Some cities in the seeded table are ambiguous(for example Lake City - US is presented 3 times) so I am just taking the first one that matches country_code+name criteria, but for production ready app we should get rid of such ambiguity.