ACCUMULO-4817 Update build plugins and parent POM
* Use Apache 19 parent POM
* Remove invalid/broken javadoc elements (specifically, invalid @author tags)
* Update configuration for newer plugins
** Exclude leaking Exceptions in public API caught by apilyzer
** Use Collections.emptySet() over Collections.EMPTY_SET caught by modernizer
** Use html5 backend over html backend for asciidoctor
* Move Maven prerequisites element from top-level POM to maven-plugin POM
* Sort modules section of POM for readability
* Drop posix config for assembly plugin (redundant with parent POM)
* Add comments related to plugins which require JDK8+
1 file changed
