Update README link to point to Mender Hub

Changelog: None

Signed-off-by: Michael Clelland <[email protected]>

README.md

@@ -67,9 +67,9 @@ issue. We thank you in advance for your cooperation.
 
 ## Connect with us
 
-* Join our [Google
-  group](https://groups.google.com/a/lists.mender.io/forum/#!forum/mender)
+* Join the [Mender Hub forum](https://hub.mender.io)
 * Follow us on [Twitter](https://twitter.com/mender_io?target=_blank). Please
   feel free to tweet us questions.
 * Fork us on [Github](https://github.com/mendersoftware)
 * Email us at [[email protected]](mailto:[email protected])
+* Connect to the [#mender IRC channel on Freenode](http://webchat.freenode.net/?channels=mender)