Fixed that modified config variables were not properly overwritten in XML
Added `pretty` parameter to clicon_options_dump
Added testcases for recursive and structure extra config files
* Internal NETCONF (client <-> backend)
* Ensure message-id increments
* Separated rpc from notification socket in same session
* Removed coverage icon from homepage since it stopped working some time ago
* Added flag names: `CLIXON_DBG_*`
* Added maskable flags that can be combined when debugging:
* `DEFAULT` = 1: Basic debug message, espcially initialization
* `MSG` = 2: Input and output packets, read datastore
* `DETAIL` = 4: Details: message dump in hex, xpath parse trees, etc
* `EXTRA` = 8: Extra detailed logs
* Test: some errors in yang-lib where content-id was in wrong place
- Change from RFC 7805: Remove revision if empty instead of sending empty revision
RFC 6022
- Added cli identity to RFC6022 transport
- Added source-host for natove restconf, bit no other sessions
- statistics and transport/source-host parameters
- extended internal NETCONF hello with transport and source-host attributes
clixon-lib,yang
- Moved all extended internal NETCONF attributes to the clicon-lib namespace
C-API:
- wrapped most attribute creation into new fn xml_add_attr()
* Fixed: [Error message seen twice in some cases](https://github.com/clicon/clixon/issues/325)
* Extended `-l` command-line option to all clixon commands with a `none` option, eg `-l n` directs logging to `dev/null`
* Note that edits to the candidate database or locks will be lost
* To force the CLI to exit if backend restarts, undef `PROTO_RESTART_RECONNECT`
* This is an effect of the fix of [Broken pipe error seen in client (cli) when backend restarts and CLICON_SOCK is recreated](https://github.com/clicon/clixon/issues/312), the CLI behavior on backend restart is changed.
* Added `eof` parameter to `clicon_rpc()` and `clicon_rpc1()` and error handling modified
* New automatic edit-mode design
* Control which modes to use with `edit-mode-default`
* Default is create edit-mode for all
* New edit-mode tree: @datamodelmode
* 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()`
* Added lastkey argument to yang_key_match()
* Fixed segv in process-sigchld
* Added ietf-yang-library to CLICON_CLI_AUTOCLI_EXCLUDE default value
* Added yang_spec_print() function
* Updated command-line usage of cli,netconf,backend apps in sync with clixon-docs user manual
* Documented differences between protocol stubs for external vs internal netconf
* Fixed: [very slow execution of load_set_file #288](https://github.com/clicon/clixon/issues/288)
* New `clixon-lib@2021-11-11.yang` revision
* Modified option: RPC stats extended with YANG stats
* Modified `clixon-config@2021-11-11.yang` revision
* Added option:
* CLICON_PLUGIN_CALLBACK_CHECK
* Enable to make plugin context check before and after all callbacks.
* Added statistics for YANG: number of objects and memory used
* Use the treeref no-copy option of CLIgen to reduce memory
* Refactored cli-generation/autocli-start code
* Refactored cligen glue functions to use cligen_eval directly (remove clicon_eval,clixon_cligen_eval)
* Added ancestor config cache indicating wether the node or an ancestor is config false or true
* Improved yang cardinality lookup
* Added yang_init(), called from all apps using yang
* Made NETCONF message handling more strict according to RFC 6241
* Set `CLICON_NETCONF_MESSAGE_ID_OPTIONAL` to true to accept omission of message-id attribute
* Fixed: [need make sure message-id exist in rpc validate #240](https://github.com/clicon/clixon/issues/240)
