Very high memory usage

[kurt1288]

I've noticed that WukongJS uses a rather large, and unexpected, amount of memory. For example, even just running 3 engines concurrently (using Cute Chess CLI) uses 3-5 gigs of RAM on my computer.

I'd like to be able to run more tests and use Wukong to do some benchmarking, but I'm not really able to run more than 1 or 2 instances at once before it stops responding to pings (because there's no memory left for it to use).