Add relationships, followed and followers
Update and refactorize sample_data.rake
Update static_pages.js
Add stats template to home and user profile
Add follow form
Add follow and unfollow forms. Integrate them and user stats with profile
Correct bug in follow_form
Add views for following and followers, including tests
Finish 11.2.4. Correct some bugs in User Controller.
Add Ajax for follow/unfollow actions. Finish implementation of following users