Add plugins to the default build to avoid warnings
Add plugins to the default build to avoid warnings

Even though the jetty plugin can't be used with java < 7 not providing
a version in those cases will generate warnings in the logs

galmeida/raven-java,buckett/raven-java,galmeida/raven-java,littleyang/raven-java,reki2000/raven-java6,buckett/raven-java,littleyang/raven-java,reki2000/raven-java6