Support attribute docstrings

[mxr]

Resolves #159

[asottile]

thanks for the patch!

I'm a little torn on this since I think it's ~slightly better to use comments than strings: #159 (comment) (and I'm pretty sure they work?)

[mxr]

Happy to close it if there's a workaround

[asottile]

Happy to close it if there's a workaround

I would need to confirm that #: works -- I don't have a sphinx project of my own to test it on though 🤔

[mxr]

@asottile should we close this?

[mbukatov]

Using a doc string instead of #: comment also allows to use rst syntax or explain the variable in multiple lines.

[asottile]

yeah I think I'll just close this