API

On potential changes of the API/ABI as detected by
[`elektra-icheck`](https://build.libelektra.org/jenkins/job/elektra-icheck),
please check following list:

- Must have been in kdbproposal.h in the previous release
  or is part of a non-core library (like libease, libmeta,...)
- Full Doxygen docu (all parameters, brief, long, examples)
- Full Testcoverage
- Still ABI/API forward-compatible
  (It is okay to break backward-compatible to add new symbols)
- All Bindings written/work (only if bindings exist for the module)
- Change is mentioned in the release notes



TODO (additional points for the future?)

- #ifdef for ELEKTRA_API present?
- add what needs to be done for symbol versioning