* Except `CLICON_RESTCONF_DIR` which remains in clixon-config.yang due to bootstrapping
* -d <dir> option removed
* This applies to both evhtp and fcgi RESTCONF
* Both can also read config from backend, and be started from backend
* You may need to move config as follows (from clixon-config.yang to clixon-restconf.yang)
* CLICON_RESTCONF_PRETTY -> restconf/pretty
* CLICON_RESTCONF_PATH -> restconf/fcgi-path
* Not backward compatible: All uses of the ca-auth callback in restconf plugins must be changed
* New version is: `int ca_auth(h, req, auth_type, authp, userp)`
* where `auth_type` is the requested authentication-type (none, client-cert or user-defined)
* `authp` is the returned authentication flag
* `userp` is the returned associated authenticated user
* and the return value is three-valued: -1: Error, 0: ignored, 1: OK
* For more info see [clixon-docs](https://clixon-docs.readthedocs.io/en/latest/restconf.html)
* New clixon-restconf@2020-12-30.yang revision
* New clixon-lib@2020-12-30.yang revision
* Added callback to process-control RPC feature in clixon-lib.yang to manage processes
* Changed behavior of starting restconf internally using `CLICON_BACKEND_RESTCONF_PROCESS` monitoring changes in enable flag, not only the RPC.
* Changed: RPC process-control output parameter status to pid
* This is an alternative to manage a clixon daemon via sudtemd, containerd or other
* One important special case is starting the clixon-restconf daemon internally
* This is how it works:
* Register a process via `clixon_process_register(h, name, namespace, argv, argc)`
* Use process-control RPC defined in clixon-lib.yang to start/stop/restart or query status on that process
* Example code in the main example
* This is an alternative to manage a clixon daemon via sudtemd, containerd or other
* One important special case is starting the clixon-restconf daemon internally
* This is how it works:
* Register a process via `clixon_process_register(h, name, namespace, argv, argc)`
* Use process-control RPC defined in clixon-lib.yang to start/stop/restart or query status on that process
* Example code in the main example
