eliminated update duplication on controllers
Merge branch 'master' into follow

Conflicts:
	config/locales/en/geo_data.yml
	config/locales/pt-BR/geo_data.yml
add following model
can follow an content only once
extract follower behavior to concern and fix #followers
Merge branch 'master' into follow

Conflicts:
	app/models/user.rb
extract #followers to Followable concern
Following model specs
add specs to concerns
move concern specs to concerns folder
delete properly followings on follower or followable destruction
extract toolbar helper + add follow component
fix application helper specs
follower#follow? method to check if user is following and object
toolbar helper refactor
following controller + follow component
followings_controller actions
followings controller spec
add follow component tests
Merge branch 'master' into follow