update examples

README.md

@@ -42,6 +42,8 @@ func main() {
 	fmt.Println(pinyin.Pinyin(hans, pinyin.Args{Style: pinyin.TONE2}))
     // 开启多音字模式 [[zhong zhong] [guo] [ren]]
 	fmt.Println(pinyin.Pinyin(hans, pinyin.Args{Heteronym: true}))
+    // [[zho1ng zho4ng] [guo2] [re2n]]
+	fmt.Println(pinyin.Pinyin(hans, pinyin.Args{Style: pinyin.TONE2, Heteronym: true}))
 }
 ```
 

examples/main.go

@@ -42,4 +42,9 @@ func main() {
 			Style: pinyin.INITIALS},
 		),
 	)
+	fmt.Println("Heteronym true TONE2: ",
+		pinyin.Pinyin(hans, pinyin.Args{Heteronym: true,
+			Style: pinyin.TONE2},
+		),
+	)
 }