setup improvmx with domain

domains/lunah.json

@@ -6,6 +6,8 @@
     "email": "lunah@lunahdev.ml"
   },
   "record": {
-    "A": ["62.171.160.186"]
+    "A": ["62.171.160.186"],
+    "MX": ["mx1.improvmx.com", "mx2.improvmx.com"],
+    "TXT": "v=spf1 include:spf.improvmx.com ~all"
   }
 }