Java Util or Log4J logging frameworks are replaced with Logback.

The following bundles will be introduced with the change:
- com.openexchange.logback.configuration
- com.openexchange.logback.extensions
- com.openexchange.logback.clt
- com.openexchange.configuration.clt
- com.openexchange.oxscripts.clt

The following package will become obselete with the change:
- open-xchange-log4j

The following bundles will be removed with the change:
- org.apache.log4j.configuration
- org.apache.commons.logging.log4j
- com.openexchange.logging.tracking