enable long polling duration thru configuration.

Author: kdcllc

src/CometD.NetCore.Salesforce/SalesforceConfiguration.cs

@@ -65,5 +65,10 @@ public sealed class SalesforceConfiguration
         /// Salesforce ReplayId for specific message.
         /// </summary>
         public int ReplayId { get; set; }
+
+        /// <summary>
+        /// Long polling duration. Default  120 * 1000.
+        /// </summary>
+        public long? ReadTimeOut { get; set; }
     }
 }

src/CometD.NetCore.Salesforce/StreamingClient.cs

@@ -171,7 +171,7 @@ private void InitBayeuxClient()
             // Salesforce socket timeout during connection(CometD session) = 110 seconds
             IDictionary<string, object> options = new Dictionary<string, object>(StringComparer.OrdinalIgnoreCase)
             {
-                { ClientTransport.TIMEOUT_OPTION, ReadTimeOut },
+                {ClientTransport.TIMEOUT_OPTION, _options.ReadTimeOut ?? ReadTimeOut },
                 {ClientTransport.MAX_NETWORK_DELAY_OPTION, 120000 }
             };