Support Medical Note Deidentification

**Is your feature request related to a problem? Please describe.**
Deidentification task: detect and mask out the private information (e.g., names, dates) in a document.

**Describe the solution you'd like**
Apply a NER-style model to detect spans that include private information.

**Describe alternatives you've considered**
A clear and concise description of any alternative solutions or features you've considered.

**Additional context**
* [Examples to explain the task](https://demo.johnsnowlabs.com/healthcare/DEID_PHI_TEXT/)
* [Finetuned RoBERTa model for the task on Huggingface](https://huggingface.co/obi/deid_roberta_i2b2)
* [Finetuned BERT model for the task on Huggingface](https://huggingface.co/obi/deid_bert_i2b2)
* [A demo on Huggingface](https://huggingface.co/spaces/obi/Medical-Note-Deidentification)