Tests: ensure all netconf requests with identityref have declared namespaces.
* This is part of fixing [Yang identityref XML encoding is not general](https://github.com/clicon/clixon/issues/90)
* 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
* Merge branch 'dcornejo-master'
* Broke out pagination callback API from state data callbacks
* New pagination callback API uses new dispatcher from netgate, thanks @dcornejo
* Register callback with: `clixon_pagination_cb_register()`
* Use accessor functions `pagination_offset()`, `pagination_limit()`, etc
* Reverted state data callback API to pre-5.3 (see C/CLI API changes below)
* Hello message semantics has been made stricter according to RFC 6241 Sec 8.1, for example:
* A client MUST send a <hello> element.
* Each peer MUST send at least the base NETCONF capability, "urn:ietf:params:netconf:base:1.1" (or 1.0 for RFC 4741)
* The netconf client will terminate (close the socket) if the client does not comply
* You can set `CLICON_NETCONF_HELLO_OPTIONAL` to true to use the old behavior of essentially ignoring hellos.
* New clixon-config@2020-03-08.yang revision
* Added: `CLICON_NETCONF_HELLO_OPTIONAL`
* The base capability has been changed to "urn:ietf:params:netconf:base:1.1" following RFC6241.
* Replaces the hardcoded "config" keyword.
* Implemented by a compile-time option called `DATASTORE_TOP_SYMBOL` option in clixon_custom.h
* Tests: added endtest to all tests. Removed all premature exits if BE=0
* 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
