Add correct url to sign in link and test for it
User edit page
Unsuccessful edits
Successful user edits, change name of signin helper function to sign_in
9.2 Authorisation
Ensure that only signed in users can access edit and upate actions in
users controller.
Ensure that the currently signed in user cannot edit other users
details; only their own details.
Friendly forwarding
9.3.1 User index
Add index action to user controller and make it available only to signed
in users.
Add link to user index for signed in users.
Add styles for user index page.
Add tests for the user index action.
Add Faker, will_paginate and bootstrap-will_paginate gems.
Sample users and pagination
9.3.4 Partial refactoring of users index view
9.4 Deleting users
Add admin users.
Add destroy action to delete users and restrict it to only by used by admin users.