Adapt network module to update OTU links only

The management of 100GE service terminating on an OTN Switch imposes to create a service directly over OTU4 links without using as direct server layer a structured ODU4. When we create/delete such a service, bandwidth parameters of the OTU4 links supporting the service must be updated (available-bandwidth, used-bandwidth).
Network module already contains an updateOtnLinks method, but that later is used for 1GE or 10GE services, it means services relying on a structured ODU4 link. The existing method updates bandwidth parameters for structured ODU4 links. It is necessary to develop a specific method to update directly bandwith parameter of the supported OTU4 links.

Acceptance criteria, Code does not bring any regressions, and is under review