Merge pull request #47 from duglin/addemail

add link to email

Author: fabiojose

README.md

@@ -372,4 +372,5 @@ Cloudevent Receiver.parse(Object, Map)
   to determine which week will have the call.
 - Slack: #cloudeventssdk channel under
   [CNCF's Slack workspace](https://slack.cncf.io/).
+- Email: https://lists.cncf.io/g/cncf-cloudevents-sdk
 - Contact for additional information: Fabio José (`@fabiojose` on slack).