can install mcping

cmd/mcping/README.md

@@ -1,5 +1,8 @@
 # mcping
 适用于Minecraft: Java Edition的ping工具
 
-Useage:
+Install with Homebrew:  
-    `mcping <hostname>[:port]`
+    ```brew tap Tnze/tap && brew install mcping```
+
+Useage:  
+    ```mcping <hostname>[:port]```