Updates the Checkstyle core to version 8.0.

Please note that this version requires Java 8 as the minimum runtime environment. This requires you to run Eclipse on a Java 8 JVM in order to use this plugin version.

This restriction does not affect the ability to analyze Java 5 or lower level source code.

This plugin version was superficially verified to be compatible with Eclipse Oxygen.

Please read the Checkstyle release notes for details on recent changes in Checkstyle.