Feature request: Dry run cshatag

[Speldosa]

To my understanding, if either the mtime or the checksum of a file (or both) have changed, "the status of the file is printed to stdout and the stored checksum is updated" (this last part is taken directly from the readme). This means that if something happened to your file that you weren't aware of (for example, if you edited it by mistake), you'll only find out when running cshatag the first time. The second time, the checksum will already have been updated and everything looks normal. I can foresee many situations where this might be a problem, for example if your computer loses power before you have a chance to inspect the output or even if you forget that you've run the program and run it again.

In rsync, you can dry run the program using the -n flag. This means that you get to see all error messages, warnings, et cetera, without actually executing the core function of the program, namely to copy files. Would it be desirable to have something similar implemented in cshatag?