public void CanGetSignature()
 {
     var signatureProvider = new SignatureProvider(PrivateCertificate, PublicCertificate);
     var messageDigest = "2012-05-19T17:27:16.630Z1234567890";
     Assert.AreEqual("YVS+Yrr280+ztQ44Qiwp0jYaRO5YJivg/HK7+/AdqUTDLYkPf2hqW6PO1n04LNOhGzAMgCgBmfkxV3fkEAnjmX/tcXU0mnwFxmQC8CjQJ/xpnXo/LDYJtkmfpaFLv0aJCWa2BSNB71Ygr8mtZQ/tach/jaaJwyWbpn+3wkUl7Zc=", signatureProvider.GetSignature(messageDigest));
 }