add validate_source method
versions are listed newest first in npackd 1.18.7
munge repos to lowercase
use the new 'list-repos' command instead of the registry
update npackd installer path, add periodic 'detect'
make repos purgable
updates for version 1.1.0
turn detect.pp off by default

It will give a (harmless, but potentially confusing) error
message on first run if npackd is being installed from scratch, so
better to have people opt in.
replace Modulefile with metadata.json