* First hello is 1.0 EOM framing, then successing rpc is chunked framing
* See
* [Netconf framing](https://github.com/clicon/clixon/issues/50), and
* [Clixon does not switch to chunked framing after NETCONF 1.1 is negotiated](https://github.com/clicon/clixon/issues/314)
* C:
* Moved netconf framing code from netconf application to clixon lib
* Test:
* New expecteof_netconf and adjusted other expect scripts to handle NETCONF 1.1 framing
* 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.
