Quote-aware string splitting

[Jeffrey Froman]

Bengt Richter wrote:

> Oops, note some spaces inside quotes near ss and missing double quotes in
> result.

And here I thought the main problem with my answer was that it didn't split
unquoted segments into separate words at all! Clearly I missed the
generalization being sought, and a more robust solution is in order.
Fortunately, others have been forthcoming with them.

Thank you,
Jeffrey