Maven plug-in enhance to permit pattern-based permissions in configuration.

Modifications to permit the Maven plug-in to allow pattern-based configuration for setting permissions on files when writing the Rock Ridge extensions (useful for setting +x to files based on patterns).

The configuration block section for this support looks like this:

                        <configuration>
                            <permissions>
                                <filePermission>
                                    <filePattern>.*\.sh</filePattern>
                                    <permission>0555</permission>
                                </filePermission>
                                <filePermission>
                                	<filePattern>.*\.p(y|l)</filePattern>
                                	<permission>0555</permission>
                                </filePermission>
                            </permissions>
                        </configuration>

This will ensure all that *.sh, *.py, and *.pl files get ugo+rx permissions during ISO generation.

(Also includes a small number of style fixes where there were indentation mismatches, and a few typos in comments).