A memory-balanced List, that more forgiving of inserting elements at index zero.

##overview:

This is my attempt to solve a niche problem, where a list is likely to be enlarged at the beginning, middle and end; but mainly on either end. Although this is not a double-queue, its still a list; can still add/remove/replace any element.
While a linked list is well suited for such a task, it might be prohibitively expensive for very large data-sets; especially byte-lists.

So my solution is to have the real data hover in the middle of the backing array, rather than at beginning as it is with a list. This makes it far cheaper to insert elements at index 0. Inserting at index 1 is still rather bad though.

##results:

'middle node is cached