Update README.md

Author: gkorland

README.md

@@ -1,6 +1,7 @@
 [![license](https://img.shields.io/github/license/RedisLabsModules/redismodule-rs.svg)](https://github.com/RedisLabsModules/redismodule-rs/blob/master/LICENSE)
 [![GitHub issues](https://img.shields.io/github/release/RedisLabsModules/redismodule-rs.svg)](https://github.com/RedisLabsModules/redismodule-rs/releases/latest)
 [![CircleCI](https://circleci.com/gh/RedisLabsModules/redismodule-rs/tree/master.svg?style=svg)](https://circleci.com/gh/RedisLabsModules/redismodule-rs/tree/master)
+[![crates.io](https://img.shields.io/crates/v/redis-module.svg)](https://crates.io/crates/redis-module)
 
 # redismodule-rs