Merge pull request linode#264 from hzoppetti/smtp-create-linode

[Update] POST linode/instances

Author: hzoppetti

openapi.yaml

@@ -2956,6 +2956,10 @@ paths:
         [Regions](/api/v4/regions) for a list
         of available Regions you can deploy your Linode in.
 
+        In an effort to fight spam, Linode restricts outbound connections on ports 25, 465, and 587
+        on all Linodes for new accounts created after November 5th, 2019. For more information,
+        see [Sending Email on Linode](https://www.linode.com/docs/email/running-a-mail-server/#sending-email-on-linode).
+
         Linodes can be created in a number of ways:
 
         * Using a Linode Linux Distribution image or an Image you created based on another Linode.