Exclude all SonarQube checks

Sonar supports @SuppressWarnings("all") to deactivate all rules.

See http://docs.codehaus.org/display/SONAR/Frequently+Asked+Questions#FrequentlyAskedQuestions-SuppressWarnings for reference.
Merge pull request #6 from Batmat/sonar-disable-check

Exclude all SonarQube checks