Fix wrong color for h2 in staging-warning banner.
Add ItsDangerous dependency.
Login template inherits from a "login-base" template.

We'll be reusing this template for the reset-pw form.
Fix ChangeControlGroup so it works on fieldsets, too, and uses Bootstrap's .error class.
Fix bug causing datetime objects returned from User to break json serialization in views
informative messages on reset-password page work.
JS reset-password form works
Real-time password match checking works on /change-password page.
Fix bug in /create causing users to not get created.

was calling requests.json as attr not method. That's 45min I won't get back :/
Reorg views page.

It is getting too big to keep track of, will try to not worry about it for now,
but we need to split it up i think into JSON and HTML views.
change-password form works, redirects to user's profile page on success.

Whole password-reset flow now works:
1. view reset form
2. submit reset form, get an emailed link
3. click link, get change-password form
4. enter new password, get logged in and redirected to profile page.