Improvement to user accounts

[oliverroick]

Proposed changes in this pull request

• Bump django-skivvy to 0.1.2
• Fixes Email verification for user accounts not recorded #766 -- Records email verification
  • The User.email_verified field is set to True when the email is verified.
• Send email and deactivate user if email is not confirmed
  • If the email is not verified within 48 hours and the user tries to login, the account is deactivated and a new confirmation email is sent. (I wasn't sure about the account deactivation, happy to change it if anyone thinks we shouldn't do it.)
  • The account will be activated when the email is confirmed.
• Fix Send confirmation email when user changes their email address #676 -- Send confirmation email when email is changed
  • When the user changes their email address a email to confirm the address is sent. The email must be confirmed within 48 hours.
• Fix Inactive account page shown but no confirmation email received #821 -- Add migration to activate user accounts when the email has been confirmed

When should this PR be merged

Anytime. But someone should thoroughly test the whole signup -> confirmation -> email change process. It easy to miss something there/

Risks

• Low risk, no migrations.

Follow up actions

None.

[oliverroick]

I've just pushed a renamed migration file (according to our new policy), this is ready to go from my end.