The network property will return an IPv4Network or IPv6Network based on the
nodecon. If the policy has host bits set, the ipaddress module will
simply ignore the host bits, so there may be unexpected results in network
comparisons.
Closes#108
Python 3.3's IPv6Network constructor does not support an expanded netmask
for specifying the network, only CIDR. Convert all netmasks to CIDR.
The code does not verify that the orignal expanded netmask from the policy
is correct; it counts all set bits in the netmask.
Also add IPv6 NodeconQuery unit tests.
