python-tests: Sphinx

[Danny Milosavljevic]

Hi Marius,

> This is fixed with e46a043ecd9f9ef46d1d44393362bb7016454544 from the
> 'python-tests' branch. Speaking of which, there are still some failing
> packages in that branch listed at:
> https://hydra.gnu.org/eval/109407?compare=master#tabs-now-fail
> 
> I'll try to take care of the remaining failures in the next week so we
> can merge this branch. Contributions are always welcome however ;-)

Can we update Sphinx in the python-tests branch please? Then some more things 
will fail...

(The reason I sent the patchsets was because Ludo suggested to test Sphinx 
breakage in the python-tests branch - that's also why it has this strange split 
into multiple patchsets...)