* RFC 8528 yang schema mount-points:
* Made expand_dbvar and cli_dbxml mountpoint-aware (RFC 8528)
* autocli supportgenerate
* Made api_path2xml and xml2api_path mount-point-aware
* Temporar fix in clixon_custom.h: XPATH_CANONICAL_SKIP_CHECK
* `xml2xpath()`: Added `apostrophe` as 4th parameter, default 0
* removed extra assert.h includes
* 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
* Removed obsolete option: `CLICON_MODULE_LIBRARY_RFC7895'
* Obsolete config options given in the confi file are considered an error
* Added section in CONTRIBUTING relating to optimzation
* Changed reset merge to implicit default values.
* This avoids a potential overwriting of explicitly set default values in the existing config
* Adapted some code to [Make cligen_* functions const ](https://github.com/clicon/cligen/pull/83)
* Test: fixed test for * Fixed: [datamodel tree generated from basemodel tree is not proper when a list has more than one key and key is of enum type](https://github.com/clicon/clixon/issues/417)
* 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 typo preventing evaluation of confirmed-commit logic in backend_startup
- fixed uninitialized variable warnings
- added details to CHANGELOG.MD
- added capabilities advertisement for confirmed-commit 1.0 and 1.1
- added xml hello message that uses only eom framing, for simplicity in asynch tests
- add stty restore after wait_restconf to fix console corruption in tests
- adjust test_confirmed_commit to drop perms and run as the invoking user. This will require running user to have permissions on /usr/local/var/example
- added CLI tests
