[REVIEW] Updated comments in run_lm_finetuning.py
I've added DistilBERT and CamemBERT models in the description of the models that can be used for fine-tuning a LM model on a custom dataset.
# [Codecov](https://codecov.io/gh/huggingface/transformers/pull/2225?src=pr&el=h1) Report
> Merging [#2225](https://codecov.io/gh/huggingface/transformers/pull/2225?src=pr&el=desc) into [master](https://codecov.io/gh/huggingface/transformers/commit/8efc6dd544bf1a30d99d4b5abfc5e214699eab2b?src=pr&el=desc) will **not change** coverage.
> The diff coverage is `n/a`.

[![Impacted file tree graph](https://codecov.io/gh/huggingface/transformers/pull/2225/graphs/tree.svg?width=650&token=9qOlN6Hb1c&height=150&src=pr)](https://codecov.io/gh/huggingface/transformers/pull/2225?src=pr&el=tree)

```diff
@@           Coverage Diff           @@
##           master    #2225   +/-   ##
=======================================
  Coverage   81.47%   81.47%           
=======================================
  Files         122      122           
  Lines       18344    18344           
=======================================
  Hits        14946    14946           
  Misses       3398     3398
```



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