Add the 'comments' field to NetworkCompartment
Add the 'comments' field to NetworkCompartment

This field should be propagated to the DW as we're planning to
present the list of valid network compartments (along with
the descriptive comments) to the users of the subnet GUI.
(they often have problems choosing the right compartment tag).

Addresses-Issue: Jira/DHCP-599

quattor/aquilon-protocols,quattor/aquilon-protocols