Usage messages for tcsh scripts

[just22]

Dear Tim,

I think that the 'usage' messages from tcsh scripts in qflow are somewhat inconsistent:

• quoting in echo commands is wrong (I often see Missing name for redirect because of <> characters and other glitches;
• the initial check on command line arguments prevents the subsequent, more verbose, help message to be printed.

This pull request tries to address most of those problems. Please let me know if the modifications are acceptable.

All the best

-- Alessandro

[RTimothyEdwards]

I see no problems with the code, so I have gone ahead with the merge. Thanks for the pull request!