Initial package

add: df to values method

add: pycox dep, improve readme (add roadmap)

draft: tests script

draft: methods to generate mixture

add: basic imputation methods

draft: Runner class, ie code to benchmark models

draft: tests

minor setup stuff

add gitignore

introduce mypy (draft status)

add todo in README

release v0.0.1: code status after submission of JDS'23 paper with first results

improve README