Change the option -o help message

[tloubrieu-jpl]

Description

since harvest writes to the registry directly, the -o option help message should be rewritten

[tdddblog]

@tloubrieu-jpl Can you be more specific. What text do you want?

[tloubrieu-jpl]

Can we just add something more specific in the help message for the -o option, saying it is only used for supplemental metadata if some are provided in the processed bundle.

@jordanpadams what do you think ?

[tloubrieu-jpl]

@jordanpadams can you give us your inputs on what the -o help message should be since harvest only writes in a output directory for supplemental metadata.

[jordanpadams]

@tloubrieu-jpl your recommendation sounds good. let's just leave the argument, but change it to say (applies to supplementer only)