Update TwilioRestClient.cs to add overloaded method in rest client

src/Twilio/Clients/TwilioRestClient.cs

@@ -64,6 +64,36 @@ public class TwilioRestClient : ITwilioRestClient
         /// <param name="region">region to make requests for</param>
         /// <param name="httpClient">http client used to make the requests</param>
         /// <param name="edge">edge to make requests for</param>
+        public TwilioRestClient(
+            string username,
+            string password,
+            string accountSid = null,
+            string region = null,
+            HttpClient httpClient = null,
+            string edge = null
+        )
+        {
+            _username = username;
+            _password = password;
+
+            AccountSid = accountSid ?? username;
+            HttpClient = httpClient ?? DefaultClient();
+
+            Region = region;
+            Edge = edge;
+        }
+
+        /// <summary>
+        /// Constructor for a TwilioRestClient
+        /// </summary>
+        ///
+        /// <param name="username">username for requests</param>
+        /// <param name="password">password for requests</param>
+        /// <param name="accountSid">account sid to make requests for</param>
+        /// <param name="region">region to make requests for</param>
+        /// <param name="httpClient">http client used to make the requests</param>
+        /// <param name="edge">edge to make requests for</param>
+        /// <param name="authstrategy">authentication strategy that will be used to make requests for</param>
         public TwilioRestClient(
             string username,
             string password,