plugin does not know about Java 8

[drXargle]

Need to override the central-parent's maven-compile-plugin configuration as it is forcing java 7. We need to have java 1.8!

[drXargle]

Ahh, it looks like the failure to cope with Java8 is not anything to do with the plugin. See Nabble issue apparently it is an old version of ANTLR which is to blame.

Issues are:

• It fails to parse files containing Java 8 specific syntax;
• It also fails to parse files containing Java 7 "diamond" operator;
• Javadocs for individual enum constants from java classes don't make it into final GroovyClassDoc metadata and hence into the docs (this works fine for groovy sources though).