Argument Handling

[pshriwise]

Description

The openmc executable's CML argument parsing is a little fragile. For example, if any flags are passed after a file/directory path they are silently ignored. It wouldn't be terribly difficult to improve this. I've used this header-only parser in a few projects and found it easy to work with.

Alternatives

We don't get a lot of complaints about the limitations here, so probably not high priority at the moment. Alternative here being the status quo.

Compatibility

I don't see any reason that a replacement for the current argument parsing could replicate exactly the expected behavior we present now.