PHP poppassd client: Change password of users with poppassd protocol

This class can be used to change the password of users, usually with POP3 accounts, by using the poppassd protocol.

It connects to a a given poppassd server and attempts to set a new password for the account of an user given the current password.

The class can return a specific error when the server did not accept the new password for being too short or being listed in a dictionary of common passwords.