Interface tweaks
Forgot password and Remember me
Reset / change password; registration email confirm; time zone
	- user gets a default time zone on registration.
		can change time zone on their account settings page.
	- password reset functionality via email, doubles as change password
		page for logged-in users.
	- on registration, you're sent an email with confirmation link.
	- Remember Me feature uses a paranoid (frequently changed) token
		and a secure cookie.
Halfway there - set up mailers, begin writing specs for rake task
Move penalization & level demotion to Rake task
	- Rake task handles penalization & level demotion by calling each user's
		#penalize_missed_deadlines and #update_level. Users that have already
		been updated today, are skipped.
	- Mailers to alert a user about missed deadlines, or send them a daily agenda
	- User migration altered to include columns for storing penalty & level change
		state until the user's next login
	- Refactoring to many specs to make them more atomistic and better in line
		with Rspec best practice