Change validation message to include the Country Code format that is failing validation (either ISO3166-A2 or -A3)

Author: bilfeldt

src/Three.php

@@ -37,6 +37,6 @@ public function passes($attribute, $value)
      */
     public function message()
     {
-        return 'Invalid country code.';
+        return 'Invalid ISO3166-A3 country code.';
     }
 }

src/Two.php

@@ -37,6 +37,6 @@ public function passes($attribute, $value)
      */
     public function message()
     {
-        return 'Invalid country code.';
+        return 'Invalid ISO3166-A2 country code.';
     }
 }