Move push update to post-receive and protected branch check to pre-receive (#1030)

* move all push update to git hook post-receive and protected branch check to git hook pre-receive

* add SSH_ORIGINAL_COMMAND check back

* remove all unused codes

* fix the import

main.go

@@ -40,5 +40,4 @@ func main() {
 	if err != nil {
 		log.Fatal(4, "Failed to run app with %s: %v", os.Args, err)
 	}
-
 }