Write specs for email story
Add confirmable module and database migration
Add two day grace period for confirming email
Adjust factory so that default user is already confirmed
New users receive Odin welcome message with Devise confirmation token
Prompt users to confirm email but allow access to site
Set up custom route for smoother user experience
Fill in migration for adding confirmable.  Because the blank one wasn't doing much...
Adjust emails to use Devise's new strategy for generating confirmation tokens
Merge branch upstream master into add_email_confirmation
Add capybara/email gem to test clicking link inside email
Sign user in and redirect them to courses page when they confirm their email
Fix migration that was changed by mistake at some point
Broken tests.
Refactor specs to follow link via regex.  Remove capybara-email gem.
Put link to resend confirmation instructions in flash message
Merge upstream master into add_email_confirmation
Minor refactoring
Change parentheses in active_for_authentication to avoid blocking previous users