Support MongoClient in Connection::isConnected()
Check for null $mongo property in Connected::getStatus()

Recent versions of the driver no longer use the $status property, so this method should likely be deprecated in the future. For the time being, at least check that the Connection's $mongo property exists (like isConnected() does) before accessing the public property.
Merge pull request #134 from doctrine/1.0.x-isConnected

Check for MongoClient and Mongo classes in Connection getters