Added tested for deallocate of ip failure.
Added test for deallocating ip addr. on one port
Added test for deallocating ip addr. w/ two associated ports
Added consistency for booleans.
Added test to allocate_ip_address twice on one port.
Added test for allocating ip address from previously deallocated address, succesfully.
Added test for allocating ip address from previously deallocated address, failing reuse_after param.
Added test for failure to allocate ip on fully allocated subnet.
pep8 cleanup
Added tenant_id as argument to allocate_ip_address
Removed redundant code.
Added test for subnet selection on ip allocation.
Added test for net_id filter on new ip address allocation.
Added test for net_id filter on deallocated ip address allocation; fixed bug in previous test.
Refactored test with _create_and_insert_net
Refactored test with _create_and_insert_subnet
Refactored test with _create_and_insert_port
Refactored test with _create_and_insert_ip