I was trying to make benchmark.py work with this latest code, and i noticed something:

For the other *BloomFilter classes, the first argument is capacity. Starting in this pull request, capacity has to be a keyword argument, and if the first argument is not a keyword argument it must be decay_time.

The problem actually comes when you try to call `__init__` on the super-class below. If capacity is not a keyword argument, or if there are any non-keyword arguments, BOOM capacity not set for CountingBloomFilter(). I think. I'm really rusty with this python class stuff.