Fix image positioning

[jplatte]

If the first and/or last commit are unwanted, I can force-push a version with just the actual image positioning changes (or you can cherry-pick those two commits).

fixes #414

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @alexcrichton (or someone else) soon.

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[jplatte]

The thumbnail classes are added back via raw html, which is labeled 'unsafe' in comrak. AFAIK, it should be perfectly fine as long as only trusted markdown input is processed though.

[nikomatsakis]

Thanks @jplatte ! Unfortunately, there are now merge conflicts, maybe you can rebase?

[jplatte]

Of course. I was expecting the merge conflicts even when opening the PR, but forgot to update this one after the other one was merged 😅

I've fixed the conflicts now.

[nikomatsakis]

@jplatte thanks for fixing the conflicts -- can you however use a rebase instead of a merge commit? (Although I wonder if GH's "rebase and merge" or "squash and merge" options would do that for you)

[jplatte]

Yeah I can rebase later. Unfortunately I can't do it in the web interface. Rebase and merge / squash and merge are only available to people with write access, and if there are no conflicts.

[jplatte]

@nikomatsakis done

[nikomatsakis]

Thanks @jplatte !