Add AUTHORS.txt

Author: yrodiere

AUTHORS.txt

@@ -0,0 +1,11 @@
+# This file lists copyright owners of the project.
+# The list is not exhaustive: other copyright owners exist.
+# See CONTRIBUTING.md for instructions regarding how to be added to this list.
+
+# Corporate contributors
+
+Red Hat, Inc.
+
+# Individual contributors
+
+# TODO initialize from relicensing data

CONTRIBUTING.md

@@ -15,10 +15,14 @@ Note that Hibernate ORM 7.0.0.Beta4 and earlier are distributed under
 To allow for potential backporting, the Hibernate team asks contributors to dual-license their contribution.
 A Pull Request template already applies the proper wording to make it easy.
 
-All contributions are subject to the [Developer Certificate of Origin (DCO)](https://developercertificate.org/).  
-
+All contributions are subject to the [Developer Certificate of Origin (DCO)](https://developercertificate.org/).
 The DCO text is available verbatim in the [dco.txt](dco.txt) file in the root directory of the ORM repository.
 
+Copyright owners are listed in [AUTHORS.txt](AUTHORS.txt).
+Contributors with a valid copyright claim can request to be added to that list
+by sending a pull request to the project's GitHub repository,
+listing at least one relevant contribution in the pull request description.
+Note: one-liner or repetitive patches may not be sufficient to claim copyright.
 
 ## Guidelines