03.4.md - use DELETE HTTP method

In REST we should use DELETE HTTP method for deletion - http://www.restapitutorial.com/lessons/httpmethods.html

en/03.4.md

@@ -141,7 +141,7 @@ When the match is made on the `HandleFunc` function, the URL is matched, so supp
 http.HandleFunc("/delete/", views.DeleteTaskFunc)
 //DeleteTaskFunc is used to delete a task, trash = move to recycle bin, delete = permanent delete
 func DeleteTaskFunc(w http.ResponseWriter, r *http.Request) {
-	if r.Method == "GET" {
+	if r.Method == "DELETE" {
 		id := r.URL.Path[len("/delete/"):]
 		if id == "all" {
 			db.DeleteAll()