I added AS number test cases, and fixed some of the special cases for truncating least-significant bits.  There are a couple of sections that Charlie needs to finish with IPv6, and it would be good to have another set of eyes on this.
I added AS number test cases, and fixed some of the special cases for truncating least-significant bits.  There are a couple of sections that Charlie needs to finish with IPv6, and it would be good to have another set of eyes on this.

rhansen/rpstir,rhansen/rpstir,rhansen/rpstir,rhansen/rpstir,rhansen/rpstir