XF2 Addons [Xon] Password Tools 3.7.5

This modification mostly follows the principles of Dan Wheelers password strength estimator zxcvbn.

• Fix "Minimum time between triggering compromised password alerts on login" operating in seconds instead of hours
• Fix cases where email 2fa would not be forced enabled on the first login request after a password is discovered as compromised
• Rename various options to be better searchable
• Adjust various option defaults to be more robust.
  • 'Minimum password length' from 8 => 10 characters
  • 'Minimum password strength' from 'very weak' to 'weak'
  • 'Pwned password minimum count (soft)' from 1 to 0
  • 'Pwned password minimum count (hard)' from 2 to 1
  • 'Pwned password cache time' from 7 to 3 days

• Fix password checks could incorrectly apply when resetting a user's password

• Improve detection of admin/automated edits for the "Enforce password complexity for admins" feature.

• Require XenForo 2.2+, drop XF2.1 support
• Actually implement cron to prune the pwned password hash cache. Old entries where already being ignored, so this will hopefully just reduce MySQL table bloat
• Fix denial of service attack by preventing too long password which can trigger factorial number of brute force password checks when using Zxcvbn
  • Update new install option defaults to more recommend values:
  • Enforce password complexity for admins
  • Enable "Length check by default, and set the "Minimum length" to 8
  • Enable "Pwned password password validation" by default