* CLICON_NACM_MODE config option, default is disabled.
* Added username attribute to all rpc:s from frontend to backend
* Added NACM backend module in example
* Backend RPC register callback function (Netconf RPC or restconf operation POST) has been changed from: `backend_rpc_cb_register()` to `rpc_callback_register()`
* Backend RPC callback signature has been changed from: `int cb(clicon_handle h, cxobj *xe, struct client_entry *ce, cbuf *cbret, void *arg)` has been changed to : `int cb(clicon_handle h, cxobj *xe, struct client_entry *ce, cbuf *cbret, void *arg)`
* Frontend netconf and restconf plugins can register callbacks as well with same API as backends.
* For preparation for authorization RFC8341
* Plugins add clixon_plugin_init() and api struct for function pointers, eg:
```
static const struct clixon_plugin_api api = {
"example",
clixon_plugin_init,
...
}
clixon_plugin_api *clixon_plugin_init(clicon_handle h)
{
return (void*)&api;
}
```
* Moved specific plugin functions from apps/ to generic functions in lib/
* New generic plugin load function: clixon_plugins_load()
* Removed client-local netconf plugins netconf_plugin_callbacks()
* This was code used before generic YANG rpc calls
* Added username to clixon handle:
* clicon_username_get() / clicon_username_set()
* Added authentication plugin callback
* Removed some obscure plugin code that seem not to be used (please report if needed!)
* CLI parse hook
* CLICON_FIND_PLUGIN
* clicon_valcb()
* Removed username to rpc calls (added below)
