Move "_source." prefix work around to API.pm parent

It's a more appropriate place and makes it work automatically
for other places that utilize the work-around.
Move release-page css to a separate less file
Mark unauthorized releases as such
Mark unauthorized releases in the version dropdown
Reorganize html tags for groups of release files

Use surrounding divs (with classes) instead of br's.
Makes handling easier.
Mark unauthorized modules (and 'provides') as such