* Follows RFC7950 Sec 15.1 and 15.6 more closely
* Fixed: [When multiple lists have same key name, need more elaborate error message in case of configuration having duplicate keys](https://github.com/clicon/clixon/issues/362)
Added new recursive minmax check for non-presence containers
This makes validation checks stricter, including check of incoming RPCs
Renamed xml_yang_check_list_unique_minmax() to xml_yang_minmax_recurse()
Fixed again: [YANG min-elements within non-presence container does not work](https://github.com/clicon/clixon/issues/355)
New API is as follows:
* `clixon_xml2file()` - Print internal tree as XML to file
* `clixon_xml2cbuf()` - Print internal tree as XML to buffer
* `clixon_json2file()` - Print internal tree as JSON to file
* `clixon_json2cbuf()` - Print internal tree as JSON to buffer
* `clixon_cli2file()` - Print internal tree as CLI format to file
* `clixon_txt2file()` - Print internal tree as text format to file
* Added `skiptop` parameter, if set only apply to children of a node, skip top node
* default is 0
* Functions are merged, ie removed and replaced with more generic functions
* `xml2json_cbuf()`: Added `skiptop` parameter: `xml2json_cbuf(..., int skiptop)`
* `xml2json()` and `xml2json_cb()` merged into `xml2json_file()` with `skiptop`
* Replace `xml2json(...)` with `xml2json_file(..., stdout, 0)`
* Replace `xml2json_cb(...)` with `xml2json_file(..., 0)`
* `clicon_xml2cbuf()`: Added `skiptop` parameter: `clicon_xml2cbuf(..., int skiptop)`
* `xml2cli()`: Added `skiptop` parameter: `xml2cli(..., int skiptop)`
* Fixed: YANG key list check bad performance
* List key check did unique "xpath" lookup instead of direct child traverse
* Fixed: YANG unique single schema-nodeid required "canonical" namespace
* E.g., `a/b` did not work even if there was default namespace in XML
* Memory leak in xpath parser
* This means that two variants are supported:
* unique "a b c", ie multiple direct chidlren
* unique "a/b/c", ie single descendants
* RFC 7950 Sec 7.8.3 is somewhat unclear
* The combination is not supported
* Netconf data-not-unique info changed to return schema nodes instead of XML for RFC7950 compliance
* 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)
* Stricter checking of outgoing RPC replies from server
* See [RPC output not verified by yang](https://github.com/clicon/clixon/issues/283)
* This lead to some corrections of RPC replies in system code
* Closer adherence to RFC 7950. Some of this is changed behavior, some is new feature.
* Essentially instead of looking at the referring leaf, context is referred(target) node
* Validation uses referred node
* Validation changed to use type of referred node, instead of just "string"
* Auto-cli
* Changed to use type of referred node for typecheck
* Completion uses referred node
* Required instance / less strict validation
* New: Leafrefs must refer to existing data leaf ONLY IF YANG `required-instance` is true
* Previous: All leafrefs must refer to existing data leaf node
* Fixed: [Autocli does not offer completions for leafref to identityref #254](https://github.com/clicon/clixon/issues/254)
* Several cases were not implemented fully according to RFC 7950
* Do not extend default values if when statements evaluate to false
* Do not allow edit-config of nodes if when statements evaluate to false (Sec 8.3.2)
* If a key leaf is defined in a grouping that is used in a list, the "uses" statement MUST NOT have a "when" statement. (See 7.21.5)
* See [yang uses's substatement when has no effect #218](https://github.com/clicon/clixon/issues/2$
* Added new revision of main example yang: `clixon-example@2020-12-01.yang`
* Fixed [YANG: key statement in rpc/notification list #148](https://github.com/clicon/clixon/issues/148)
* Do not check uniqueness among lists without keys
