Bug 2826

I was able to do something odd by incorrectly using RFT command-line tool. A
user-friendly fix here would stop someone like me from messing up.

Here's what I did:

bin/rft -h ned-0.isi.edu -r 9000 -file ./transfer.xfr

Where "./transfer.xfr" is my transfer request. The correct parameter above would
have been "-f" instead of "-file". Though I made this error the interface still
accepted my transfer request file as if I had used "-f" and then overwrote my
transfer request file with the RFT resource EPR. So now my transfer reqeust is gone.

In this case, it was ok because my xfr file was trivial, however, if it had been
more substantial I would have had a problem.

A better behavior might be to stop me from doing this and give a cmd-line error.