search links to most recent version *even* if that version was yanked

[pnkfelix]

Currently searching for "pandoc" on crates.io yields results that links to v0.5.3 of the pandoc crate.

But if you follow that link, you get the "This crate has been yanked" page.

Someone who wants to use the pandoc crate has to then go through the "view all versions" link to get to a non-yanked version.

It would be a better user experience if the search results linked to the most recent non-yanked version of a crate.

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Note that this issue is somewhat distinct from #145 ; I read #145 as saying that if all versions of a crate have been yanked, then no entry should show up at all for it.

[carols10cents]

Yes, I think this is a duplicate of #510 though.