Firefox certificates not being deleted

[tresf]

We currently use an ill-advised but previously working technique for removing QZ Tray SSL certificates from Firefox by searching by nickname using findCertByNickname. At some point, this technique broke, newer Firefox versions don't seem to support this technique. There's also a API for searching by email (findCertByEmailAddress), but that seems to be broken as well so we'll have to find it manually.

The newly proposed method is to manually iterate over all certificates and purge those with support@qz.io in the email address.

Sample autoconfig code:

var certdb = getCertDB();
var certs = certdb.getCerts();
var enumerator = certs.getEnumerator();
while (enumerator.hasMoreElements()) {
   var cert = enumerator.getNext().QueryInterface(Components.interfaces.nsIX509Cert);
   if(cert.containsEmailAddress ("${vendor.email}")) {
      certdb.deleteCertificate(cert);
   }
}

Next, the various installer would need to pass vendor.email in as a replacement string.
* Linux/Apple
* Windows

Edit: We should be safe without touching the cert logic since ant will configure this email address at packaging time.