cards: remove Blizzard card

Bad idea to reply to everyone who says Blizzard
card_bot: better names for constants
move version to readme
generate_card_csv: create BANNED_CARD_LIST
Revert "move version to readme"

This reverts commit 139aeb1ec3fb4a3e3369552510968b47c7f3f492.

We need it for our user agent