Program Repair Shop

`GrabFileList`

How to keep the file lists from the various InputDIRs separate?
Another option: Do not mingle them in the first place
Have GrabFileList read just one directory at a time:

        sub GrabFileList {
          my $dir = shift;
          opendir FILELISTDIR, $dir;
          my @files = readdir FILELISTDIR;
          closedir FILELISTDIR;
          return @files;
        }

This will necessitate calling it multiple times, and similar changes to CopyFiles:

        for my $dir (@InputDIR) {
          my @files = GrabFileList($dir);
          # ...
          CopyFiles($dir, @files);
        }

This makes good sense, because both functions presently contain this for loop
By abstracting it out, we can remove the loop from both functions
This will result in a cleaner overall flow