C++ API docs are rendered incorrectly

[tdenniston]

This appears to be a bug introduced in Sphinx with some version >= 1.6.8. Currently it does not work to specify a specific Sphinx version in ReadTheDocs:

readthedocs/readthedocs.org#3829
(which seems to be blocked by conda/conda#6845)

Example of incorrect rendering:

We'll either have to wait for this to be fixed in Sphinx, or wait for pinned Sphinx versions to work on RTD.

[tdenniston]

This appears to have been fixed (I think by a newer version Sphinx).