fix: coding style and file format for chapter 9.

eBook/exercises/chapter_9/main_greetings.go

@@ -1,22 +1,22 @@
-package main
-
-import (
-	"fmt"
-	"./greetings/greetings"
-)
-
-func main() {
-	name := "James"
-	fmt.Println(greetings.GoodDay(name))
-	fmt.Println(greetings.GoodNight(name))
-	
-	if greetings.IsAM() {
-		fmt.Println("Good morning", name)
-	} else if greetings.IsAfternoon(){
-		fmt.Println("Good afternoon", name)
-	} else if greetings.IsEvening(){
-		fmt.Println("Good evening", name)
-	} else {
-		fmt.Println("Good night", name)
-	}
-}
+package main
+
+import (
+	"./greetings/greetings"
+	"fmt"
+)
+
+func main() {
+	name := "James"
+	fmt.Println(greetings.GoodDay(name))
+	fmt.Println(greetings.GoodNight(name))
+
+	if greetings.IsAM() {
+		fmt.Println("Good morning", name)
+	} else if greetings.IsAfternoon() {
+		fmt.Println("Good afternoon", name)
+	} else if greetings.IsEvening() {
+		fmt.Println("Good evening", name)
+	} else {
+		fmt.Println("Good night", name)
+	}
+}