Add example

example/main.go

@@ -0,0 +1,22 @@
+package main
+
+import "github.com/go-logr/zapr"
+import "go.uber.org/zap"
+
+type E struct {
+	str string
+}
+
+func (e E) Error() string {
+	return e.str
+}
+
+func main() {
+	log := zapr.NewLogger(zap.NewExample())
+	log = log.WithName("MyName").WithValues("user", "you")
+	log.Info("hello", "val1", 1, "val2", map[string]int{"k": 1})
+	log.V(1).Info("you should see this")
+	log.V(3).Info("you should NOT see this")
+	log.Error(nil, "uh oh", "trouble", true, "reasons", []float64{0.1, 0.11, 3.14})
+	log.Error(E{"an error occurred"}, "goodbye", "code", -1)
+}