sphinx is not rendering enum members

[mattsb42-aws]

This worked originally; at some point it changed.

sphinx-doc/sphinx#1609

I tried just slotting this into our auto-generated tree, but it looks like this will only work once we re-structure the docs to be better organized and less reliant on "just auto-generate everything and dump it in a big pile".

[bpeake-illuscio]

To tack onto this: If you have defined any methods on the enum class, they are not being printed either.

[karlw00t]

Thanks for the details! We'll look into it.

[mattsb42-aws]

Experimenting with this on another project, I found that the missing syntax is the members and undoc-members values.

.. automodule:: aws_encryption_sdk.identifiers
   :members:
   :undoc-members: