Update README.md

vanity: contract address and (decimal) token IDs have 31415926 prefix

chore: script to set base image URI

chore: symlink images based on contract code hash

beauty: centre instead of align equations

feat: vanity address with 0x314159 prefix

perf: loop limit.go to equivalent gas of other methods

feat: ability to change a token metadata name

feat: complete tokenURI() with base image URI

feat: LaTeX for generating token images

feat: onlyOwner on external mint()

feat: draft NFT contract

chore: change Go module location and pidentities package comment