This library provides a strict, immutable, thread-safe, single-ended, bounded
queue. When the insert limit is reached and a cons is attempted, this BQueue
automatically drops old entries off its end. Thus, writes always succeed and
never block.
This data structure is intended as a "sliding window" over some stream of data, where we wish old entries to be naturally forgotten. Since this is an immutable data structure and not a concurrent queue, we provide instances for the usual useful typeclasses with which one can perform analysis over the entire "window".