NFD

For the first release we would need to have an equivalent of AUTOREG functionality: whenever a client connects to the hub, hub should automatically set up FIB entry for pre-configured prefix towards the new face.

The implementation should be done as a separate nfd-autoreg-server app, which uses FaceMgmt protocol to receive notifications about new faces and FibMgmt protocol to insert appropriate entries to the NFD's FIB.

nfd-autoreg-server should have it own configuration file, which specifies list of prefixes for automatic registration and whitelist/blacklist of IP addresses/networks to enable/disable AUTOREG functionality (e.g., autoreg MUST not be enabled for faces between hubs that run routing protocol).