Add in optional callbacks for when dynamic resources are setup and deleted.
Add in optional callbacks for when observe subscriptions start and stop.
Add in optional callbacks for when the observe counter is updated (can be
ratelimited) for a resource as well as track when a resource is deleted.
Add is support for new functions
Main functions with libcoap tracking support are
coap_persist_startup()
coap_persist_stop()
coap-server has -t option to track observe information.
UDP sessions supported, as well as OSCORE over UDP.
Documentation updated
libcoap tracking support (as opposed to application tracking) is configurable.