Did some cleaning

I realized that my difficulties adding instance variables to the base class came from the fact that I was trying to add them in the module that I was *extending* instead of including. As such, I now have a blocking method that only blocks for those threads spawned by the object in question. I also realized that the changes needed to make the recursive Mandelbrot set drawing work also allowed me to parallelize with a traditional loop, so that was exciting - even if only because it shows the flexibility of my strategy.

I'll try and get the code online (maybe github?) and get links up if people want to see it.