Pyarrow Bugfix

• Bump pyarrow = "^3.0.0" to resolve new dependency conflicts from ongoing pyarrow dev
• Bump python requirement to python = "^3.8"
• fix automated poetry versioning to use poetry-dynamic-versioning = "^0.10.0" (still waiting for native plugin version)

v0.2.0 Minor Update

This release primarily deals with re-factoring repository structure, and adding preliminary tools/quality of life updates.

• New readme with demo of basic features
• Native download for scispacy v0.2.4 pre-trained models
• CordTasks dataclass interface (tasks-as-data)
• interface with Univ. Korea's covidAsk, with BERN interface+viz to come
• automatic compatibility checks with cord19_cdcs release tags (use cv-download --overwrite to get most recent patch)
• switch to pyarrow engine for supporting list objects in parquet (e.g. authors, keywords, etc); see this issue