ed78dcf webui: use command_dialog as a base class for password dialog

Authored and Committed by pvoborni 5 years ago
    webui: use command_dialog as a base class for password dialog
    
    refactoring for:
    https://fedorahosted.org/freeipa/ticket/4997
    
    Reviewed-By: Martin Babinsky <mbabinsk@redhat.com>