Lionel N authored Aug 31, 2017 and Jehan committed Sep 01, 2017

Supports for password protected PDF. When an encrypted PDF is opened, a
dialog box asks for the password.
When an encrypted PDF is opened, a dialog box asks for the password.
The password dialog box loops as long as the password is wrong (or user
hits CANCEL/escape key)

Reviewed and fixed by Jehan.