Set correct count after unioning two bloom filters

[grafke]

After unioning two bloom filters, the count of the resulting bloom filter was set to 0. I updated the union method to update the self.count of the result as well.

[jaybaird]

This sets the correct count for union, but will need to also have it set for intersection in this case. I can take a look at adding this soon.

Another possibility is removing the count entirely and moving to a more pressure based system for growing the filter that isn't exposed to the API. Let me think about this some more.

[grafke]

I added the correct count in the intersection method as well.