RFC: Poroposed packaging format for the models

[dlazesz]

As e-magyar (emtsv) is transitioning to use python packages instead of GIT submodules and LFS I've created a proposal for packaging emBERT models.

You can see the proposal here: https://github.com/dlt-rilmta/emBERT-models/tree/packaging

With a slight modification in emBERT models could be checked as installed python packages too in order to extract the location of the actual files via the model_dir attribute (e.g. embert.models.szeged_maxnp_bioes.model_dir ).

Packaging enables us to simplify the install process and separately version the models from the main module.

Please review it and share your thoughts. Also feel free to modify the code or merge.

[DavidNemeskey]

Will do after the paper deadline.