feat(accounts): set up django-cities-light

- Will provide future address info for user input
- Limit cities to Brazil only
feat(accounts): load some Brazil cities into a test fixture
feat(accounts): introduce User Address modelling
feat(accounts): add User Address edit functionality
feat(common): bind CoffeeScript to our django-pipeline setup
feat(accounts): add CoffeeScript configuration
feat(accounts): enhance state/city lists' labels

django-cities-light provide very verbose __unicode__ methods for both
Region and City models. Our <select>s must have the labels cleaned up.
PS: this might need performance enhancements later.
feat(*): set up bower for providing 3rd-party front-end libs
feat(*): add a pipeline endpoint for 3rd-party js libs
feat(*): add jQuery 2.1.1 to bower dependencies
feat(accounts): filter cities options upon state selection
fix(accounts): fix user address migration
feat(*): update django-cities-light
fix(accounts): import unicode_literals to support py2.7
fix(accounts): simplify 'login required' tests
fix(accounts): avoid requests to retrieve form instances @ tests

This avoids a request to retrieve a form instance.
fix(accounts): enhance user address tests integrity
feat(accounts): add tests for cities import filter signal
fix(accounts): test address forms city grouping
fix(accounts): move form-related tests into `test_forms`