Add Python GPUProcessor example

[beatreichenbach]

This just adds a basic example to the docs that would have helped me find what I needed.

Fixes #2164

I am probably going to fail EasyCLA so please feel free to edit and take over if it's easier.

edit: Is there any workaround that allows me not having to use my email address for the EasyCLA? Can I use my beatreichenbach@users.noreply.github.com address?

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: beatreichenbach / name: Beat Reichenbach (1ece5e8)
• ✅ login: doug-walker / name: Doug Walker (f2a5d11, 64fb7b4)

[zachlewis]

Suggested change

	A full example of a GPUProcessor can be found in th OCIO source: ``src/apps/pyociodisplay``.
	A full example of a GPUProcessor can be found in the OCIO source: ``src/apps/pyociodisplay``.

[zachlewis]

edit: Is there any workaround that allows me not having to use my email address for the EasyCLA? Can I use my beatreichenbach@users.noreply.github.com address?

I'm not sure. I know for the individual CLA registration process, you have to provide legit contact information; but I think as long as github is able to validate your signed commits, you can sign with your @users.noreply.github.com address. Put it this way: whenever I use github's web interface for any git-fu, it creates commits signed with my users.noreply.github.com address that pass the EasyCLA + DCO checks. (Even though I still use the e-mail address I signed up with whenever I manually sign commits...)

[beatreichenbach]

Okay, I completed the EasyCLA and pushed a signed off commit. Hopefully I did everything right.
Thanks for the spellcheck!

[doug-walker]

Thanks for making things easier for others @beatreichenbach , this is exactly how open source is supposed to work!

By the way, the failing CI tests are unrelated to your changes.