Wine Mono packaging updates

[Vincent Povirk]

> The instructions don't say that the previous MSI-installed wine-mono
> must be removed to upgrade an existing prefix with shared wine-mono, so
> I expect that most users wishing to use the shared wine-mono will simply
> extract the shared package and then use the new wine version on their
> existing prefixes to upgrade and hit this issue.

That's not how it's supposed to work, but I may have made a mistake in
the search process.