Readme update to add link to project roadmap (knative#2916)

Author: lkingland

README.md

@@ -25,3 +25,7 @@ We are always looking for contributions from the Function Developer community.
 For a list of all help wanted issues in Knative, take a look at [CLOTRIBUTOR](https://clotributor.dev/search?project=knative&page=1).
 
 The `func` Working Group meets @ 10:00 US Eastern every Tuesday, we'd love to have you! For more information, see the invitation on the [Knative Team Calendar](https://calendar.google.com/calendar/u/0/embed?src=knative.team_9q83bg07qs5b9rrslp5jor4l6s@group.calendar.google.com).
+
+## Roadmap
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+Our project roadmap can be found: https://github.com/orgs/knative/projects/49