added following/unfollowing functionality
Merge branch 'following-users'

Conflicts:
	app/assets/stylesheets/relationships.css.scss
	app/controllers/relationships_controller.rb
	app/controllers/users_controller.rb
	app/models/micropost.rb
	app/models/relationship.rb
	app/models/user.rb
	app/views/static_pages/home.html.erb
	app/views/users/show.html.erb
	config/routes.rb
	db/schema.rb