public IList<GnuKey> GetKeysForSigning()
        {
            var crypto = new PgpCrypto(new CryptoContext());
            List<GnuKey> keys = new List<GnuKey>();

            foreach (string key in crypto.GetPublicKeyUserIdsForSign())
            {
                var match = Regex.Match(key, @"<(.*)>");
                if (!match.Success)
                    continue;

                GnuKey k = new GnuKey();
                k.Key = match.Groups[1].Value;
                k.KeyDisplay = key;

                keys.Add(k);
            }

            return keys;
        }