* Added check for libxml in configure';
* Added clixon_util_regexp utility function
* Yang state get improvements
* Integrated state and config into same tree on retrieval, not separate trees
* Added cli functions `cli_show_config_state()` and `cli_show_auto_state()` for showing combined config and state info.
* Added integrated state in the main example: `interface/oper-state`.
* Added performance tests for getting state, see [test/test_perf_state.sh].
* For backward compatibility, load of startup and running set CLICON_XML_NS_STRICT to false temporarily.
* Added three-valued return values for several validate functions where -1 is fatal error, 0 is validation failed and 1 is validation OK.
* This includes: `xmldb_put`, `xml_yang_validate_all`, `xml_yang_validate_add`, `xml_yang_validate_rpc`, `api_path2xml`, `api_path2xpath`
* Added new xml functions for specific types: `xml_child_nr_notype`, `xml_child_nr_notype`, `xml_child_i_type`, `xml_find_type`.
* `CLICON_YANG_DIR` is changed from a single directory to a path of directories
* Note CLIXON_DATADIR (=/usr/local/share/clixon) need to be in the list
* CLICON_YANG_MAIN_FILE Provides a filename with a single module filename.
* CLICON_YANG_MAIN_DIR Provides a directory where all yang modules should be loaded.
* Change all @datamodel:tree to @datamodel in all CLI specification files
* If you generate CLI code from the model (CLIXON_CLI_GENMODEL).
* For backward compatibility, define CLICON_CLI_MODEL_TREENAME_PATCH in clixon_custom.h
* Removed return value ymodp from yang parse functions (eg yang_parse()).
* New config option: CLICON_CLI_MODEL_TREENAME defining name of generated syntax tree if CLIXON_CLI_GENMODEL is set.
* Improved unknown handling
* Configure option `CLICON_YANG_DIR` is changed from a single directory to a path of directories
* Note CLIXON_DATADIR (=/usr/local/share/clixon) need to be in the list
* Except clixon-config module due to bug reported below
* Bug: Top-level Yang symbol cannot be called "config" in any imported yang file.
* datastore uses "config" as reserved keyword for storing any XML whoich collides with code for detecting Yang sanit
* Added urn:ietf:params:netconf:capability:yang-library:1.0
* Thanks SCadilhac for helping out, see https://github.com/clicon/clixon/issues/39
* uri_percent_encode() and xml_chardata_encode() changed to use stdarg parameters
* Changed Netconf hello to single capabilty urn:ietf:params:netconf:capability:yang-library:1.0 according to YANG 1.1 RFC7950 Sec 5.6.4.
* Set by option: CLICON_MODULE_LIBRARY_RFC7895 - enabled by default
* Option CLICON_MODULE_SET_ID is set and changed when modules change.
