Add method to retrieve a host_netblock via its identifier
Add method to retrieve a host_netblock via its identifier

pombredanne/mirrormanager2,pombredanne/mirrormanager2,pombredanne/mirrormanager2,Devyani-Divs/mirrormanager2,Devyani-Divs/mirrormanager2,pombredanne/mirrormanager2,Devyani-Divs/mirrormanager2,Devyani-Divs/mirrormanager2