fix: coding style and file format for chapter 6.

eBook/exercises/chapter_6/10to1_recursive.go

@@ -1,13 +1,15 @@
-package main
-
-import "fmt"
-
-func main() {
-	printrec(1)
-}
-
-func printrec(i int) {
-	if i>10 { return }
-	printrec(i+1)
-	fmt.Printf("%d ", i)
-}
+package main
+
+import "fmt"
+
+func main() {
+	printrec(1)
+}
+
+func printrec(i int) {
+	if i > 10 {
+		return
+	}
+	printrec(i + 1)
+	fmt.Printf("%d ", i)
+}