Specifically, two things:
- make drracket more careful to not crash when aspell
doesn't behave, and
- have a more careful test when clicking the menu item
(it now does a trial run of aspell instead of just
looking for the binary)
closes PR 13242 (I realize there is still a feature
request mentioned in the audit trail of that PR, but
since the main problem is fixed, I'll consider that
to just be something separate)