Torch update

[loggrado]

Overhaul torch instructions.

• Split into two pages: Install, and Docker
• Install page exclusively discusses methods for installing pytorch
• Docker:
  • Provide example dockerfiles (BEST PRACTICE) instead of encouraging "live builds" and commiting
  • [TEMPORARY] Remove sections on building from source, and upstream docker image
    • I was unable to reproduce either of these "installation" methods.
    • Have reached out to Peng Sun (who builds the base images) for help in revamping these sections

[lpaoletti]

Please rebuild it.
I'll review when it builds

[lpaoletti]

@loggrado
I'll review it when the docs build. Is that ok?

[peterjunpark]

Hi @loggrado. I understand you want to replace docs/how-to/3rd-party/pytorch-install.rst with docs/how-to/3rd-party/pytorch/install.rst and pytorch/docker.rst.

Docs URLs are generated based on file structure. Deleting pytorch-install.rst is problematic because other ROCm documentation and very many ML blog posts on the portal refer to this URL.

I fixed the merge conflicts as the PR is very stale, but I didn't accept the removal of this file. If the decision is made to actually remove pytorch-install.rst, you'll have to do it again.

@lpaoletti Please review the new content.