Support micro batching in channels

[asarkar]

It'd be nice to be able to receive (or send) multiple values at once from the channel, something like channel.receive(n). For the case when n elements are not available, there could be an overloaded version channel.receive(n, duration) and even channel.receive(n, shouldBlock); shouldBlock=false would immediately return a batch with fewer than n elements.

[adamw]

I would have to re-check with the paper basing on which the channels algorithm is implemented, but I think that a channel.receive(n) would amount to calling receive n-times. That is, no optimization of the multi-receive is actually possible, you'd have to execute the receive algorithm n times.