Add issuer options to cert-show and cert-find
Add options to cert-show and cert-find for specifying the issuer as
a DN, or a CA name.
Also add the issuer DN to the output of cert-find.
Part of: https://fedorahosted.org/freeipa/ticket/4559
Reviewed-By: Jan Cholasta <jcholast@redhat.com>
Reviewed-By: Martin Babinsky <mbabinsk@redhat.com>