public static void mkdirs(final Path dir) {
        if (!Files.isDirectory(dir)) {
            try {
                Files.createDirectories(dir);
            } catch (final IOException e) {
                throw new FileUtilException("Unable to make directory: " + FileUtil.getCanonicalPath(dir));
            }
        }
    }
Similar to the unix touch command. Sets the last modified time to now if the file
exists else, creates the file

@throws IOException
stroom-util/src/main/java/stroom/util/io/FileUtil.java