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