add link tests
Make a basic User model (include secure passwords)
Finish user signup
Add SSL in production
Add option for gravatar image size
bundle install missing gems
8.1.1 - add signin routes & controller
8.1.3 - add signin view & tests
8.1.3 - re-add signin view & tests
8.1.5 - add signin test for flash errors
stage for listing 8.15 - remember token
staging for 8.2.2.  also, add remember token for remembering users during signin.
stage for 8.2.4.  Add functionality for current-user
stage for 8.2.5. Also add navbar that corresponds to current_user
stage for 8.2.6 - signout.  Didn't finish test for auto signin after registration because tutorial info was vague.
stage for 8.3.  Add destroy session/signout function
add files from some time earlier in chapt 8?