Checks the answer to the secret question and allows the user to reset their password if it's correct.

• Accessed at index.php?action=reminder;sa=secret2
• Encrypts the answer given by the user and checks it against the encrypted SecretAnswer in the database
• Throws an error if the user doesn't have a secretQuestion (shouldn't happen, but you never know)
• Validates all the input data and throws an error if something is invalid
• Changes the user's password to whatever they chose if the answer is correct
• After the password is changed, redirects them to the login page with their username and password filled in