tests: add startstop condition detector tests, fix behavior

tests: add test for address detector

fix: make colorama dependency of vunit propagated

fix: bugs in address detector

fix: compilation errors

feat: add i2c slave state entity

feat: add i2c misc entities

feat: add i2c rx, tx entities

feat: add utility entities

Delay, metastability filter, open drain buffer, synchronous edge detector

chore: use python from nixpkgs instead of poetry

Initial commit