readme add sample code

README.md

@@ -21,4 +21,36 @@ all methods of zap:
 
 ## example
 
-you can find example in [examples](./examples).
+you can find example in [examples](./examples).
+
+```go
+// cat ./examples/default/main.go
+package main
+
+import "github.com/chalvern/sugar"
+
+func main() {
+
+	sugar.Debug("default development sugar of chalvern")
+	myCustomLogger()
+	myCustomLogger2()
+
+	sugar.InitProductionSugar()
+	sugar.Debug("should not be printed")
+	sugar.Info("default production sugar of chalvern")
+	myCustomLogger()
+	myCustomLogger2()
+}
+
+func myCustomLogger() {
+	myLogger := sugar.NewLoggerOf("my_custom_logger")
+	myLogger.Info("log of myCustomLogger info")
+	myLogger.Warn("log of myCustomLogger warn")
+}
+
+func myCustomLogger2() {
+	myLogger := sugar.NewLoggerOf("my_custom_logger_2")
+	myLogger.Info("log of myCustomLogger2 info")
+	myLogger.Warn("log of myCustomLogger2 warn")
+}
+```