add ontonotes_conll dataset

[richarddwang]

Introduction of the dataset

OntoNotes v5.0 is the final version of OntoNotes corpus, and is a large-scale, multi-genre,
multilingual corpus manually annotated with syntactic, semantic and discourse information.

This dataset is the version of OntoNotes v5.0 extended and used in the CoNLL-2012 shared task
, includes v4 train/dev and v9 test data for English/Chinese/Arabic and corrected version v12 train/dev/test data (English only).

This dataset is widely used in name entity recognition, coreference resolution, and semantic role labeling.

In dataset loading script, I modify and use the code of AllenNLP/Ontonotes to read the special conll files while don't get extra package dependency.

Some workarounds I did

1. task ids
   I add tasks that I can't find anywhere semantic-role-labeling, lemmatization, and word-sense-disambiguation to the task category structure-prediction, because they are related to "syntax". I feel there is another good name for the task category since some tasks mentioned aren't related to structure, but I have no good idea.

2. dl_manage.extract
   Since we'll get another zip after unzip the downloaded zip data, I have to use dl_manager.extract directly inside _generate_examples. But when testing dummy data, dl_manager.extract do nothing. So I make a conditional such that it manually extract data when testing dummy data.

Help

Don't know how to fix the building doc error.

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint.

[lhoestq]

Awesome ! Thanks for adding the dataset :)

The dataset card and dataset script are already really good, thanks ! I left a few comments:

[lhoestq]

Thank you ! Just did some minor changes

[lhoestq]

The CI fail is unrelated to this dataset, merging :)