Parse dub{-registry} + dconf.org for the contributors list too

[wilzbach]

Needs dlang/tools#278

So while I was doing this, I realized that this is maybe not the best idea for a default built as:

• dconf.org is 400M big
• these three repositories now would be cloned by default when someone runs the default target or e.g. html

Other ideas? Should add a FLAG like DEPLOYMENT_BUILD which adds these repos?
CC @CyberShadow

[dlang-bot]

Thanks for your pull request, @wilzbach!

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[CyberShadow]

I don't think this change is at all necessary.

[wilzbach]

Fair enough. I don't like the prospect of cloning the giant dconf.org repo either