[Smartfrog-developer] OptionSet gets an empty constructor

[Steve L. <ste...@hp...>]

I am about to add an empty constructor to OptionSet(), so that you can
create one and fill it in, instead of having to construct (and parse) an
argument string.

This will let us run smartfrog under Junit; we cannot use main() as it
as it has a habit of calling exit() whenever it is unhappy, which of
course kills junit.