Built-in Comparator doesn't work for referenced.list file.

[redxeth]

In working on a project today found that if ONLY the referenced.list file that gets generated by origen program command is different from its reference, then Origen.app.stats.changed_files is not updated.

It updates Origen.app.stats.changed_patterns instead but since there really wasn't a pattern generation executed then the number of completed patterns is 0 so the changed file isn't caught.

Usually this isn't a problem since if your program is messed up enough to cause a difference in the referenced.list then the program files will fail the difference check and be caught. But we had a strange case where the referenced.list used as a reference changed and thus a change was indicated in the log, but the overall comparison didn't fail.