Fixes MCHECKSTYLE-253: Upgrade to checkstyle 5.9 for Java 8 compatability

Including IT checks for the existence of a typical error message with
older checkstyle messages (expecting EOF, found &apos;return&apos;).
This dismisses all other messages of checkstyle for the class.

git-svn-id: https://svn.apache.org/repos/asf/maven/plugins/trunk@1632982 13f79535-47bb-0310-9956-ffa450edef68