Validate plug-in names before loading
Validate plug-in names before loading

On Windows, we only want to load .dll files are plug-ins, even though
there might be other support files present in the plug-in directory.

madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal