[IDEA] Add a mechanism for unlocking user accounts

[feathersct]

When updating the password requirements for lockout periods, if a user accidentally meets the strike count then their user is locked out. Currently there's no mechanism to unlock their account, except to go into the db and reset the strike count manually.

I need this feature so I can unlock user accounts when they've accidentally met the strike count.

It'd be great to have a button that admins could use to unlock a user's account within the Administrator.