F deprecate yamlapi

Summary

The yamlapi should be obsolete in future (see Issue #62 (closed)). Warnings to all functions of this API were added.

Focus

All changes were made in the yamlapi. Tests for the warning were added.

Test Environment

tox

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CHANGELOG.md

@@ -22,8 +22,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Deprecated ###
 
-* `id_query(ids)` in apiutils
-* The whole yamlapi with the following functions:
+* `id_query(ids)` in apiutils (to be removed with >=0.5.4)
+* The whole yamlapi with the following functions (to be removed with >=0.5.4):
   * `append_sublist` 
   * `kv_to_xml`
   * `dict_to_xml`