Introduce license header templates

To support multiple license headers simultaneously, a license folder
for holding licenses is introduced. The original "Bosch Software
Innovations GmbH" license header is set as default and the Siemens
license header is added as an example for a further valid license.

Signed-off-by: Christian Storm <christian.storm@siemens.com>
Signed-off-by: Himanshu Kumar Singh <himanshu.singh@siemens.com>

pom.xml

@@ -211,7 +211,10 @@
             <artifactId>license-maven-plugin</artifactId>
             <version>2.11</version>
             <configuration>
-               <header>LICENCE_HEADER_TEMPLATE.txt</header>
+               <header>licenses/LICENSE_HEADER_TEMPLATE_BOSCH.txt</header>
+               <validHeaders>
+                   <validHeader>licenses/LICENSE_HEADER_TEMPLATE_SIEMENS.txt</validHeader>
+               </validHeaders>
                <excludes>
                   <exclude>**/README</exclude>
                   <exclude>3rd-dependencies/**</exclude>
@@ -226,6 +229,7 @@
                   <exclude>**/Dockerfile</exclude>
                   <exclude>**/.sonar/**</exclude>
                   <exclude>docs/src/main/resources/**</exclude>
+                  <exclude>**/LICENSE*</exclude>
                </excludes>
                <mapping>
                   <scss>JAVADOC_STYLE</scss>