* First version of clixon-autocli.yang semantics
* Default rules for module exclusion, list-keywords, completion, treeref-state
* Specialized rules for compress and exclusion of modules
* See [autocli documentation](https://clixon-docs.readthedocs.io/en/latest/cli.html#autocli)
* Obsoleted and moved autocli config options from clixon-config.yang to clixon-autocli.yang as follows:
* `CLICON_CLI_GENMODEL`, use: `autocli/module-default=false` instead
* Removed `clicon_cli_genmodel()`
* `CLICON_CLI_GENMODEL_TYPE`, use `autocli/list-keyword-default` and compress rules instead)
* Removed `clicon_cli_genmodel_type()`
* `CLICON_CLI_GENMODEL_COMPLETION`, use `autocli/completion-default` instead
* Removed `clicon_cli_genmodel_completion()`
* `CLICON_CLI_AUTOCLI_EXCLUDE`, use `autocli/rule/operation=exclude` instead
* `CLICON_CLI_MODEL_TREENAME`, use constant `AUTOCLI_TREENAME` instead
* Removed `clicon_cli_model_treename()`
* New YANG functions: yang_single_child_type, yang_find_namespace_by_prefix, yang_str2key
* Changed return values of yang_find_prefix_by_namespace
* Merged `cli_cli2xml()` into `cli2xml()`
This include plugin module init and exit functions
New type: clixon_plugin_t exposed via public API while struct clixon_plugin is private
- Makefile changes for static linkage using "LINKAGE=static"
- Moved nacm external init to later stage in backend_main
* The existing autocli does not support modes, complete paths must be given, eg: `set a b c d 42`.
* In the new auto-cli, automatic modes are present at each YANG syntax node level, eg the above can be given as: `edit a b c; set d 4; top`
* The existing CLI API remains, the new API is as follows: `cli_auto_edit()`, `cli_auto_up()`, `cli_auto_top()`, `cli_auto_show()`, `cli_auto_set()`, `cli_auto_merge()`, `cli_auto_create()`, `cli_auto_del()`.
* See `test/test_cli_auto.sh` for an example of the new API, and `apps/cli/cli_auto.c` for the source code of the new callback API.
* Documentation will be appear and full integration with the main example.
* Added inline state field to clixon-example.yang
* Added new clicon_data_cvec_*() API for generic cvec structs
