Add script example to the README.

v2/README.md

@@ -161,6 +161,36 @@ fmt.Println(msg, err)
 // &{mychannel hello} <nil>
 ```
 
+To use Lua scripting:
+
+```go
+client := redis.NewTCPClient(&redis.Options{
+	Addr: ":6379",
+})
+defer client.Close()
+
+setnx := redis.NewScript(`
+    if redis.call("get", KEYS[1]) == false then
+        redis.call("set", KEYS[1], ARGV[1])
+        return 1
+    end
+    return 0
+`)
+
+run1 := setnx.Run(client, []string{"keynx"}, []string{"foo"})
+fmt.Println(run1.Val().(int64), run1.Err())
+
+run2 := setnx.Run(client, []string{"keynx"}, []string{"bar"})
+fmt.Println(run2.Val().(int64), run2.Err())
+
+get := client.Get("keynx")
+fmt.Println(get)
+
+// Output: 1 <nil>
+// 0 <nil>
+// GET keynx: foo
+```
+
 You can also write custom commands:
 
 ```go