DIP11: Automatic downloading of libraries

[Adam D. Ruppe]

Andrei Alexandrescu:
> http://www.wikiservice.at/d/wiki.cgi?LanguageDevel/DIPs/DIP11

This is pretty similar to what my build.d does, except I assume
the base url instead of letting it be specified. (I considered having
a metadata file, but since I control the server anyway, I don't need
it for me!)

What I like is that it's a very simple idea that has no central
point of failure.