Clean up BOTMETA.yml (#44574)

This PR includes:
- Removal of maintainers that are listed as author in the module
- Removal of entries that do not extend the original author list
- Move ignored-statement to namespace/directory (where useful)
- In some cases, fix the authors-list or add missing github id

We end up with a list of exceptions/additions and a large set of
namespace/directory maintainers or team of maintainers.

Some entries could be further improved by discussing with some
maintainers.

lib/ansible/modules/identity/opendj/opendj_backendprop.py

@@ -21,7 +21,7 @@ description:
    - It will check first via de get-backend-prop if configuration needs to be applied.
 version_added: "2.2"
 author:
-    - Werner Dijkerman
+    - Werner Dijkerman (@dj-wasabi)
 options:
     opendj_bindir:
         description: