Custom Sphinx Extension: PandasCompat

[isVoid]

This PR adds a custom sphinx extension PandasCompat. This extension adds two new rST directives to cudf docs code base.

.. pandas-compat::
.. pandas-compat-list::

The former creates a new section in cudf docstring specifically to demonstrate the deviation that cudf has to pandas. The second directive collects all these sections and compile as a separate list. For example, in MultiIndex.get_loc:

The new section is rendered as an Admonition tag.

And there's a new separate page called Pandas Compatibility Notes that collects all notes in a single page.

Note that we can introduce a link in this page to the original source.

[isVoid]

This PR is at primitive stage, but should be ready to receive reviews (both code-wise and page aesthetics).

[codecov]

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[quasiben]

Thanks for looking at this @isVoid -- this is really great! I especially like having both compat notices inlined with api docs and a separate page.

cc @jfpuget

[isVoid]

@galipremsagar I think it would also be great to review this extension in the context of pydata sphinx theme.

[vyasr]

This is great! Also you weren't kidding, the Sphinx TODO example covers our needs here almost exactly. Since you largely just mimicked it I don't have a ton to comment on, but I learned a lot reading it.

[galipremsagar]

@vyasr could you have another look at it before we merge this?

[vyasr]

This looks great to me! One minor comment @isVoid if you can easily verify that it would be nice but it's not a blocker.

Once this is merged we need to make a plan for making use of this new directive in the rest of our docstrings, how should we do that? Perhaps we should make a follow-up issue to track that work.

[vyasr]

I believe the trailing :: is redundant in this case since you're not passing any arguments, but it's probably fine to leave it as is unless you're in a position to test and remove fairly quickly.

[harrism]

This looks great to me! One minor comment @isVoid if you can easily verify that it would be nice but it's not a blocker.

Once this is merged we need to make a plan for making use of this new directive in the rest of our docstrings, how should we do that? Perhaps we should make a follow-up issue to track that work.

@vyasr or @isVoid please open an issue for this.

[harrism]

@gpucibot merge