include description, railway deploy button and command to run in development in README

README.md

@@ -1 +1,12 @@
-# geoip
+# GeoIP
+
+## A maxmind geoip api server with auto db refresh
+
+[![Deploy on Railway](https://railway.app/button.svg)](https://railway.app/template/LiUOsa?referralCode=bSruGU)
+
+## Development
+
+```bash
+air # with air
+go run main.go # without air
+```