less warnings for non-empty directories during purge

import java.io.File;

import java.io.IOException;

import java.nio.file.DirectoryNotEmptyException;

import java.nio.file.FileVisitResult;

import java.nio.file.FileVisitor;

import java.nio.file.Files;

        public FileVisitResult postVisitDirectory(Path dir, IOException exc) throws IOException {

            try {

                Files.delete(dir);

            } catch (DirectoryNotEmptyException dnee) {

                getLog().debug("The folder will not be deleted as it is not empty: " + dir);

            } catch (IOException ie) {

                getLog().debug(ie);

                getLog().warn("The folder failed to delete: " + dir);