fix broken ra.xml schema
Merge pull request #1731 from asimarslan/feature/master/issue1727

fix broken ra.xml schema
Made some changes to checkstyle configuration
Fixed some checkstyle issues
Deactivate checkstyle on mapreduce by default
Fine tuned checkstyle.xml with Chris.
Merge pull request #1738 from gregrluck/master

Fine tuned checkstyle.xml with Chris.
Made usage of checkstyle.xml / suppression.xml possible in Maven and IntelliJ plugin