Baai glm
add glm model
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_17113). All of your documentation changes will be reflected on that endpoint.<|||||>As requested on slack, I just had a quick look at your PR. It's in good shape! :blush: 

Regarding the fast tokenizer part, to check its validity, I suggest we take a first stab by looking at the results of the tests you created. For the moment, it seems to me that we can't leverage the tests files you added -at least with the CI. To fix it, I think you need to add the model you are creating to the main init file (this one: https://github.com/huggingface/transformers/blob/main/src/transformers/__init__.py). To know what to add maybe the easiest way as Lysander mentioned earlier is to see on another branch the additions that are made when you add a model from another model with the cli command `transformers-cli add-new-model-like` (cf [this discussion](https://huggingface.slack.com/archives/C036A8ECY79/p1647333073740149)).

Then, concerning the tokenizer fast, I already see 2 small things: 1. it will be necessary to add a converter (cf the discussion we had [here](https://huggingface.slack.com/archives/C036A8ECY79/p1650009413440189?thread_ts=1649381592.438409&cid=C036A8ECY79)) and 2. I have the impression that there are new special tokens added - like `ENC_token`, `sop_token`, `eop_token`, `gMASK_token` etc (but I am not sure to see where they are used in the code). 

Don't hesitate to ask for more details! I'm here to help