[BLOOM] Update doc with more details
# What does this PR do?

Addressing https://huggingface.co/bigscience/bloom/discussions/86 
I think that we should add the full list of the trained languages on the documentation so that we can refer to that whenever any user will have any question related to the trained languages

cc @ydshieh @Muennighoff 

cc @cakiki <|||||>_The documentation is not available anymore as the PR was closed or merged._<|||||>I would remove it, as it doesn't matter for the architecture, which these docs explain afaict? It's just an artefact of the data the models are trained on, hence it's arldy on the pretrained model & dataset READMEs. If someone were to release a BLOOM architecture model trained on different languages, this would be confusing imo.

Also should probably say `Pre-trained BLOOM models were officially released in the following sizes:`, as theoretically it's available in whatever version/size someone wants, just need to train it from scratch

<|||||>Not sure if the model doc is restricted to the architecture.

- `T5` has `## Example scripts` section
- Some models include `training` and `generation` sections, for example, `t5` or `m2m_100`
- `Marian` has a `## Naming` section

But I agree that we can probably just have something similar to `Marian` doc:

```
Note: The list of languages used in training can be found [here](link to model card page).
```<|||||>Okay I agree with both points!
IMO we can just specify that this list of languages is only relevant for bloom models stated on the doc, and for custom bloom models one should refer to the corresponding model card.
<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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