Add CNCF trademark guidelines and update community members (#560)

Signed-off-by: Naga Ravi Chaitanya Elluri <[email protected]>

README.md

@@ -129,6 +129,7 @@ Please read [this file]((CI/README.md#adding-a-test-case)) for more information
 
 
 ### Community
-Key Members(slack_usernames/full name): paigerube14/Paige Rubendall, mffiedler/Mike Fiedler, ravielluri/Naga Ravi Chaitanya Elluri.
-* [**#krkn on Kubernetes Slack**](https://kubernetes.slack.com)
-* [**#forum-chaos on CoreOS Slack internal to Red Hat**](https://coreos.slack.com)
+Key Members(slack_usernames/full name): paigerube14/Paige Rubendall, mffiedler/Mike Fiedler, tsebasti/Tullio Sebastiani, yogi/Yogananth Subramanian, sahil/Sahil Shah, pradeep/Pradeep Surisetty and ravielluri/Naga Ravi Chaitanya Elluri.
+* [**#krkn on Kubernetes Slack**](https://kubernetes.slack.com/messages/C05SFMHRWK1)
+
+The Linux Foundation® (TLF) has registered trademarks and uses trademarks. For a list of TLF trademarks, see [Trademark Usage](https://www.linuxfoundation.org/legal/trademark-usage).