Added vanity registry address to readme

Author: jaydenwindle

README.md

@@ -4,9 +4,9 @@ This repository contains the reference implementation of [ERC-6551](https://eips
 
 **This project is under active development and may undergo changes until ERC-6551 is finalized.**
 
-The current ERC6551Registry address is `0x284be69BaC8C983a749956D7320729EB24bc75f9`.
+The current ERC6551Registry address is `0x000000006551c19487814612e58FE06813775758`.
 
-For the most recently deployed version of these contracts, see the [v0.3.0](https://github.com/erc6551/reference/releases/tag/v0.3.0) release. We recommend this version for any production usage.
+For the most recently deployed version of these contracts, see the [v0.3.1](https://github.com/erc6551/reference/releases/tag/v0.3.1) release. We recommend this version for any production usage.
 
 ## Using as a Dependency