specl: improve --help output.
specl: improve --help output.

* specl/version.lua.in (M["--help"]): Improve --help output
formatting, and correct an inaccuracy in --verbose description.

Signed-off-by: Gary V. Vaughan <f9023000f29773649f3850298becb9544b5fd6a9@gnu.org>

gvvaughan/specl