Use autolabel extension

[benjaoming]

It would be nice to use the autolabel extension as suggested by @humitos

I have a very specific case to motivate it. Supposing you are writing a blog post that refers to a section in a previous blog post. This has already happened to me. I then have to edit the previous blog post to add a label. I can't recall the details, but I'm pretty sure it has made the RSS feed confused that previous entries are edited.

(Similar issues will continue to happen with Intersphinx if we blog posts refer docs that change later on, so it's still an issue we should pay attention to)