Fixed a bug in DataView still using the deprecated `unsubscribe`

lib/DataView.js

@@ -39,8 +39,8 @@ DataView.prototype.setData = function (data) {
 
   if (this._data) {
     // unsubscribe from current dataset
-    if (this._data.unsubscribe) {
-      this._data.unsubscribe('*', this.listener);
+    if (this._data.off) {
+      this._data.off('*', this.listener);
     }
 
     // trigger a remove of all items in memory