Fix for circular reference error

On create_subnet, the quantum client passes in arguments to create a subnet
with, including dns_nameservers and allocation_pools, which do not exist in
quark's database models. SQLAlchemy causes these fields to exist in the
model created and result as basic objects in the response object, which in turn
is choked upon by oslo-incubator's jsonutils.to_primitive function.
Fixes issue #46: use int explicitly
Merge pull request #48 from asadoughi/subnet_ip_fix

Fixes issue #46: use int explicitly
Merge pull request #49 from asadoughi/master

Fix for circular reference error
Playing with tenants
Prototype of the default nets is working. Jank, but works
Started moving the strategies into their own pluggable driver ala policy
Remaps the subnets network back to the parent network if one matches
Reworked the format again, and generates a reverse index now for faster lookup
Now leverages the reverse strategy correctly, and should always be masking the child network UUIDs
The parent network no longer needs to exist