Add make docs and doc building instructions

[driazati]

This moves the doc instructions to a .md so GitHub knows how to render it nicely in the browser. It also adds a Python runner tests/scripts/ci.py that will invoke the same scripts as in CI to build the docs, along with some options to make local development nicer (i.e. most people probably don't want to wait around for the C++/typescript docs to build if they are editing the Python docs). Simple usage can be done from the makefile with the defaults, or the script can be invoked directly for more control

# these are the same
make docs
python tests/scripts/ci.py

python tests/scripts/ci.py --help

# build all language docs and run checks
python tests/scripts/ci.py --precheck --full

[driazati]

This should be equivalent on recent versions of Sphinx: https://github.com/sphinx-gallery/sphinx-gallery/blob/master/sphinx_gallery/gen_gallery.py#L150-L156

[areusch]

just curious, what was the problem being solved by adding this here? right now we're mostly worried about the Sphinx version pinned in ci-gpu, so while I think it's good for us to support a more recent sphinx, we need to dig ourselves out of relying on ci-gpu for all docs purposes (e.g. and use it only when doing a full docs build including gpu-dependent galleries) before we should think about making the docs flow work on a modern ubuntu.

[driazati]

just laziness, initially I was using a more recent version of Sphinx that needed this fix to run but with using the versions from ci-gpu this isn't necessary

[areusch]

thanks @driazati, a couple questions. moving the README.txt to markdown is a great idea.

[areusch]

rather than do this, should we add a tool to run pip freeze on ci-gpu and then use this as a constraints file to locally install these deps? my concern is that adding a requirements.txt with pins may drift.

[driazati]

Removed the requirements.txt and added 2 building flows, one that uses a short script and relies on ci-gpu and one that just uses it to generate the list of dependencies. Given that creating a list is pretty simple and anyone developing the docs probably has access to Docker I think it's fine to not commit the dependencies list for now and let people generate it directly.

For now this works OK but the makefile + bash setup doesn't seem tenable for the larger goals of allowing developers to reproduce CI easily, we might want to consider a Python runner similar to Rust's x.py added a Python runner instead

[areusch]

just curious, what was the problem being solved by adding this here? right now we're mostly worried about the Sphinx version pinned in ci-gpu, so while I think it's good for us to support a more recent sphinx, we need to dig ourselves out of relying on ci-gpu for all docs purposes (e.g. and use it only when doing a full docs build including gpu-dependent galleries) before we should think about making the docs flow work on a modern ubuntu.

[tqchen]

Thanks @driazati . Considering the fact that not everybody have a GPU machine in their env. It would be good to "promote" the instruction for building docs without running tutorials(which can actually be most of the cases).

This will also answer the common question "how do i build docs quickly on my local env in a few mins"

https://github.com/apache/tvm/blob/main/tests/scripts/task_sphinx_precheck.sh#L39 does that/

[areusch]

thanks @driazati, did a round of review here