remove deprecated comments for markdown generation

update README

fix licence line in python files

clean up .pyc file

Rename Libra into Primary

update cargo dependencies (except ed25519-dalek and rand)

Tiny cleanups / wart-removal

Removing env_logger from fastpay_core

Removing log from fastpay_core

Update version dependencies

Also introduces a workaround to https://github.com/dalek-cryptography/ed25519-dalek/issues/126 (see workspace Cargo.toml)

Update license