Documentation missing -r (remove files after successful combination) description

[wfcooke]

I was not aware of the -r option to combine_restarts, so I wasn't using it.
If my memory is correct combine_restarts used to remove the distributed files after a successful combine, but no longer does by default.

combine_restarts -h gives a list of the options, but until I looked at the code, I didn't use or know of the -r option.

Describe the solution you'd like
Add the -r description into the help function.