This change updates the backdating logic to only be applied to the
NotBefore date and not the NotAfter date when the certificate is
short lived. Thus when such a certificate is issued, it will not be
immediately expired. Long lived certificates continue to have the
same lifetime as before.
Consolidated all certificate lifetime logic into the
PermissiveSigningPolicy.policy method.
Signed-off-by: Monis Khan <mok@vmware.com>
