added real_ip and cloudflare_real_ip middlewares, fixed that some middlewares does not work properly

internal/net/http/status_code.go

@@ -0,0 +1,7 @@
+package http
+
+import "net/http"
+
+func IsSuccess(status int) bool {
+	return status >= http.StatusOK && status < http.StatusMultipleChoices
+}