GitLab

* add tutorials

* add new context, modify and delete existing docs

* remove duplicate labels

* modify layout and more nits

* address comments

* fix merge conflicts

* adding a shard-aware GradScaler wrap, credits to Sean Naren for the idea
* adding stubs & explanations in the documentation

- removed experimental warning as we have validated it on cifar and
imagenet, transformer is looking good so far too.
- fixed API doc formatting
- make it consistent with the other code in the repo
- tested by making the doc locally and inspect the results

* various fixes, no more issues with `make html` and more API fields should be populated