[Users] Installing bogofilter and other plugins

[Adrian]

> But loading the bogofilter plugin there will not work if Adrian really
> only installed claws-mail because the plugins are not included in the
> claws-mail package in Debian based distributions but are packaged to
> individual plugin packages. And there's also a meta package
> claws-mail-plugins which depends on all plugin packages.

Thanks to all, Dave, Brad, Paul and Manfred.

As you may have seen, I found those other claws-mail packages including
the bogofilter one.

I have to say that the official plugins page, though under Downloads in
the navbar, doesn't mention these packages, and just has a link to
download the source package and build Claws Mail from source.  A
sentence about the plugin packages and where to find them would save
people a lot of time!

Adrian