add supportsCRLs method back in

Stack/Opc.Ua.Core/Security/Certificates/DirectoryCertificateStore.cs

@@ -417,6 +417,11 @@ namespace Opc.Ua
             return StatusCodes.BadCertificateRevocationUnknown;
         }
 
+        /// <summary>
+        /// Whether the the store support CRLs.
+        /// </summary>
+        public bool SupportsCRLs { get { return true; } }
+
         /// <summary>
         /// Returns the CRLs in the store.
         /// </summary>

Stack/Opc.Ua.Core/Security/Certificates/ICertificateStore.cs

@@ -66,6 +66,11 @@ namespace Opc.Ua
         /// </summary>
         StatusCode IsRevoked(X509Certificate2 issuer, X509Certificate2 certificate);
 
+        /// <summary>
+        /// Whether the store supports CRLs.
+        /// </summary>
+        bool SupportsCRLs { get; }
+
         /// <summary>
         /// Returns the CRLs in the store.
         /// </summary>

Stack/Opc.Ua.Core/Security/Certificates/X509CertificateStore.cs

@@ -165,6 +165,8 @@ namespace Opc.Ua
             }
         }
 
+        public bool SupportsCRLs { get { return false; } }
+
         public StatusCode IsRevoked(X509Certificate2 issuer, X509Certificate2 certificate)
         {
             throw new ServiceResultException(StatusCodes.BadNotSupported);