Implement resource directory (RD) server
Description
Implement a resource directory (RD) service on Linux to centrally store resource as they are being announced to the network. Allow queries on resource types and keep data up-to-date.
- RD service based on libcoap on Linux
- Systemd service unit for RD
- Keep data up-to-date (e.g. alive timer after initial addition, alive timers, etc)
- Enhance command line utility to query RD and display its data