1. Added #ifdef extern "C" to public header files.
2. Changed variables that are key words in c++, to different names (like ns instead of namespace).
3. Changed char* to const char* for constant strings.
* In summary, a user registers an upgrade callback per module. The callback is called at startup if the module is added, has been removed or if the revision on file is different from the one in the system.
* The register function has removed `from` and `rev` parameters: `upgrade_callback_register(h, cb, namespace, arg)`
* The callback function has a new `op` parameter with possible values: `XML_FLAG_ADD`, `XML_FLAG_CHANGE` or `XML_FLAG_CHANGE`: `clicon_upgrade_cb(h, xn, ns, op, from, to, arg, cbret)`
* A generated clispec including state (default @datanodestate) also generated along with the config clispec tree (default @datanode)
* New mode `GT_HIDE` set by option `CLICON_CLI_GENMODEL_TYPE` to collapse non-presence containers that only contain a single list
* Added a prfix for cli_show_config/cli_show_auto so that it can produce parseable output
* Thanks dcornejo@netgate.com for trying it out and suggestions
* Removed xml-stats non-config data (replaced by rpc `stats` in clixon-lib.yang)
* Added option `CLICON_YANG_UNKNOWN_ANYDATA` to treat unknown XML (wrt YANG) as anydata.
* Reduced memory for attribute and body objects, see `XML_NEW_DIFFERENTIATE` compile-time option.
* Optimized cbuf handling in parsing and xml2cbuf functions.
* Optimized xml scanner to read strings rather than single chars
* Optimized xml_merge for the case of disjunct trees.
* Added: stats RPC for clixon XML and memory statistics.
* Added: restart-plugin RPC for restarting individual plugins without restarting backend.
* xml-stats moved from clixon-config.yang as state data to an rpc `datastats` in clixon-lib.yang
* Experimental: restart_plugin
* Two new plugin callbacks added
* ca_daemon: Called just after a server has "daemonized", ie put in background.
* ca_trans_commit_done: Called when all plugin commits have been done.
* Note: If you have used "end" callback and usign transaction data, you should probably use this instead.
* Two new plugin callbacks added
* ca_daemon: Called just after a server has "daemonized", ie put in background.
* ca_trans_commit_done: Called when all plugin commits have been done.
* `clixon_netconf_error(category, xerr, msg, arg)` removed first argument -> `clixon_netconf_error(xerr, msg, arg)`
* Renamed utility function `clixon_util_insert()` to `clixon_util_xml_mod()` and added merge functionality.
* Fixed: Insertion of subtree leaf nodes were not made in the crrect place, always ended up last regardless of yang spec (if ordered-by system).
