Fix license apache2 (#7)

PR:

Final Apache 2.0 license file set,
Updated and improved images describing full SDK flow.
---------

Co-authored-by: JorgeEcheva26 <jorge.echevarriauribarri.practicas@telefonica.es>

LICENSE

-Apache Software License 2.0
- 
-Copyright (c) 2021, Stavros Kolometsos
-Copyright (c) 2024, Jorge Echevarría, Daniel García
- 
-Licensed under the Apache License, Version 2.0 (the “License”);
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
- 
-http://www.apache.org/licenses/LICENSE-2.0
- 
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an “AS IS” BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-
 Apache License
                            Version 2.0, January 2004
                         http://www.apache.org/licenses/
@@ -204,6 +187,7 @@ Apache License
       identification within third-party archives.
 
    Copyright 2022 Telefónica Innovación Digital, Fogus Innovations & Services P.C. and ETSI.
+   Copyright (c) 2021, Stavros Kolometsos
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.