- updated markdown doc
- moved file list management back into the Aggregator, and added a getFiles() method.
- simplified the self-referencing listFiles() method due to internal private _files param use
- listFiles returns the file count rather than the file list now, however considering support for method chaining and returning the class instance itself instead.
- completed support for all listed output formats
- updated example.php to work with the new method params
- updated example output with new Aggregator code hints