Fix help message formatting for validateDrpy.py

[wmwv]

Pass formatter_class=argparse.RawDescriptionHelpFormatter to
argparse.AggumentParser.

[jonathansick]

This looks like a very useful change.

The only optional improvement is to note that using the triple double-quotes, with the contents indented to the function scope, means that the help message is intended by four spaces.

A way to get around that is to assemble the help text line by line:

description = \
    'Calculate and plot validation Key Project Metrics from the LSST SRD.' \
    'http://ls.st/LPM-17\n' \
    'Produces results to:' \
    'STDOUT' \
    '    Summary of key metrics' \
    'REPONAME*.png' \
    '    Plots of key metrics.  Generated in current working directory.' \
    'REPONAME*.json' \
    '    JSON serialization of each KPM.' \
    'where REPONAME is based on the repository name but with path separators' \
    'replaced with underscores.  E.g., "Cfht/output" -> "Cfht_output_"' \

or maybe a saner approach is to make description a global level variable, outside the function scope (this is a script after all, so it's cool, and then the triple double-quotes won't introduce any unintentional indents.

[wmwv]

Thanks for the suggestion. I've moved the description definition up to global scope for this script.