add support for xoauth & xoauth2

lib/Connection.js

@@ -58,7 +58,9 @@ function Connection(config) {
     connTimeout: config.connTimeout || 10000,
     keepalive: (typeof config.keepalive === 'boolean'
                 ? config.keepalive
-                : true)
+                : true),
+    xoauth:config.xoauth,
+    xoauth2:config.xoauth2,    
   };
 
   this._sock = undefined;