+ <!-- move all logging to log4j 2-->
+ <!-- <dependency>
+ <groupId>org.apache.logging.log4j</groupId>
+ <artifactId>log4j-slf4j-impl</artifactId>
+ <version>${log4j.version}</version>
+ </dependency> -->
+ <!-- move all log4j2 logging to the current slf4j implementor,
+ !!! never use together with log4j-slf4j-impl on classpath => endless circle -->