Suppress the warning from tomcat

Tomcat don't recognize logger without <code>org.jboss</code> category:

```
log4j:WARN No appenders could be found for logger (org.jboss.logging).
log4j:WARN Please initialize the log4j system properly.
```

You can test using master version and running <code>mvn tomcat7:run</code>

This change was discussed before in #406