[Audacity-quality] Reset effects

[Steve F. <ste...@gm...>]

An issue that crops up time to time, particularly when a user decides
to "try out" a new version of Audacity before removing their old
version - "phantom" effects that don't work.

It would be useful to be able to reset which effects are enabled
without having to send users looking for hidden folders.

Perhaps a "Factory defaults" button in the Plug-in Manager?

Steve