No hook for reordering of nodes in a subqueue

The only available hook for reordering is hook_nodequeue_swap($sqid, $nid). looking at the code, this hook is only called from nodequeue_queue_swap. nodequeue_queue_swap is itself only called from nodequeue_subqueue_shuffle, nodequeue_queue_up and nodequeue_queue_down. Any other way to reorder a subqueue (ie. nodequeue_queue_front, nodequeue_queue_back, nodequeue_set_subqueue_positions and nodequeue_save_subqueue_order) will not trigger any reordering hook.

This means a module can ot plug itslef into the reordering of subqueue like it can for node addition and removal.

We need this feature for one of our project (we need to track changes in queues) and I'm willing to work on a patch for this. Calling hook_nodequeue_swap() mutliple times for each nodes in a reordered subqueue seems inneficient. I plan to add an additional hook_nodequeue_reorder($sqid) triggered after completion of any reordering operation.