7.1 - 7.1.2: Debuging and Rails envronments / A Users resource
7.1.3 Testing the user show page (with factories)
7.1.4 A Gravatar image and a sidebar
7.2 - 7.2.2 !!!!: Signup form / Usinf form_for

- test fail; there's somewhat strange.
7.3 - 7.3.2 strong parameters:

one of two fail test resolved; one, create user still remain fail at this stage.
7.3.3 Signup error messages
7.4.1 The finished signup form
7.4.2 - 7.4.3: The flash - The first signup