Don't use $reset flag with node_load()

Refer to #1967266: Stop flushing entire entity load cache bins unnecessarily for more details.

Wherever possible, only flush the necessary entities from the cache, using entity_get_controller($entity_type)->resetCache(array($entity_id));

In this module quiz_insert() sometimes does this:

$old_quiz = node_load($node->clone_from_original_nid, NULL, TRUE);

I haven't examined what's going on here in detail, but assuming it is necessary for the load cache to be bypassed for this particular load, then use entity_load_unchanged($entity_type, $id) to load it (which runs the resetCache() and load() sequence for that single ID).

(Or if the reset was actually to flush something else, then just flush that thing explicitly.)