Switch documentation to rust-random.github.io and prepare 0.6.1

[dhardy]

This is based on top of the commit in #651 so only one of these needs to be merged.

Possible solution to #646.

[dhardy]

Lets try this tweak to shields and doc. If it doesn't go down well we can always revert the change.

[newpavlov]

Looks like a fine temporary solution, but personally I would prefer if docs.rs will be used if possible. Is there any good solutions for cross-crate links which will work with docs.rs?

[dhardy]

Well, absolute links work. Otherwise maybe we can fudge it with deeper relative links? For example ../../../../rand_pcg/*/rand_pcg/type.Pcg32.html from here might work... though it'll probably break local builds and what we host on github.io.

Or maybe we can use a script to fix things up... could be ugly.

There's also the html_root_url parameter modified here, but I don't know if that helps us.

[dhardy]

Found an issue I created six months ago: rust-lang/docs.rs#204