Add an encrypted signal to QNAM and QNetworkReply to allow applications
to perform additional checks on the certificate chain beyond those done
as part of the standard SSL validation. This allows things like
certificate change notification to be implemented for QNAM as they can
be for QSSLSocket currently.
Change-Id: I693e3e6fec8b7040379b7e7f1f819550e6b2617f
Reviewed-by: Peter Hartmann <phartmann@rim.com>