GitLab

* Added model cards for 4 models

Added model cards for:
- roberta-base-bulgarian
- roberta-base-bulgarian-pos
- roberta-small-bulgarian
- roberta-small-bulgarian-pos

* fixed link text

* Update README.md

* Create README.md

* removed trailing bracket

* Add language metadata
Co-authored-by: Julien Chaumond <chaumond@gmail.com>