Added User Authenticate, user_id for posts
	modified:   Gemfile
	modified:   Gemfile.lock
	modified:   app/controllers/application_controller.rb
	modified:   app/controllers/posts_controller.rb
	modified:   app/models/post.rb
	modified:   app/models/user.rb
	modified:   app/views/posts/index.html.erb
	new file:   db/migrate/20140513075616_add_user_id_to_posts.rb
	modified:   db/schema.rb