Adding notes about query logging to readme

Author: jenssegers

README.md

@@ -313,3 +313,9 @@ You can also perform an unset on a model.
 You may easily cache the results of a query using the remember method:
 
     $users = User::remember(10)->get();
+
+### Query Logging
+
+By default, Laravel keeps a log in memory of all queries that have been run for the current request. However, in some cases, such as when inserting a large number of rows, this can cause the application to use excess memory. To disable the log, you may use the `disableQueryLog` method:
+
+    DB::connection()->disableQueryLog();