use stable kop-common version

pom.xml

@@ -31,7 +31,7 @@
 	<parent>
 		<groupId>de.itvsh.kop.common</groupId>
 		<artifactId>kop-common-parent</artifactId>
-		<version>2.1.0-SNAPSHOT</version>
+		<version>2.1.0</version>
 		<relativePath/> <!-- lookup parent from repository -->
 	</parent>