License update

• clean LGPL-3 license following GNU recommendations in COPYING and COPYING.LESSER
• all authors with their roles mentioned in AUTHORS.md file
• added LICENSE section in readme
• added LICENSE.md file with UFZ copyright notice
• COPYING, COPYING.LESSER, LICENSE.md and AUTHORS.md automatically detected by hatch and added to sdist and wheels

LICENSE.md

+# SOFTWARE LICENCE
+
+FINAM is an open-source component-based model coupling framework for environmental models.
+
+## Copyright Notice
+
+Copyright © 2023, FINAM developers from Helmholtz-Zentrum für Umweltforschung GmbH - UFZ. All rights reserved.
+
+***The code is a property of:***
+
+> Helmholtz-Zentrum für Umweltforschung GmbH - UFZ<br/>
+> Registered Office: Leipzig<br/>
+> Registration Office: Amtsgericht Leipzig<br/>
+> Trade Register Nr. B 4703<br/>
+> Chairman of the Supervisory Board: MinDirig'in Oda Keppler<br/>
+> Scientific Director: Prof. Dr. Georg Teutsch<br/>
+> Administrative Director: Dr. Sabine König
+
+***Contact:***
+
+- FINAM Admins (E-mail: <finam@ufz.de>)
+- Martin Lange (E-mail: <martin.lange@ufz.de>)
+- Sebastian Müller (E-mail: <sebastian.mueller@ufz.de>)
+- Stephan Thober (E-mail: <stephan.thober@ufz.de>)
+- Sabine Attinger (E-mail: <sabine.attinger@ufz.de>)
+
+> Department Computational Hydrosystems (CHS)<br/>
+> Helmholtz Centre for Environmental Research - UFZ<br/>
+> Permoserstr. 15<br/>
+> 04318 Leipzig, Germany
+
+This program is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along with this program.
+It can be found in the files `COPYING` and `COPYING.LESSER` provided with this software.
+The complete GNU license text can also be found at < https://www.gnu.org/licenses/>.
+
+## Redistribution
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+- Redistributions of source code must retain the above copyright notice, the list of conditions for redistribution and modification as well as the following GNU Lesser General Public License.
+- Redistributions in binary form must reproduce the above copyright notice, this list of conditions, the following GNU Lesser General Public License and the modification conditions in the documentation and/or other materials provided with the distribution.
+- Neither the name of Helmholtz-Zentrum für Umweltforschung GmbH - UFZ, nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+## Modification
+
+If software is modified to produce derivative works, such modified software should be clearly marked, so as not to confuse it with the version available from Helmholtz-Zentrum für Umweltforschung GmbH - UFZ.