Update Registry to v2.2.0

Add '2.2.0' and '2.2' tags.  Update '2' tag to point to 2.2.

Remove 2.1 and 2.1.1 as they will not get newer releases, but will still be
available from the hub.

Signed-off-by: Richard Scothern <[email protected]>

library/registry

@@ -7,6 +7,6 @@ latest: git://github.com/docker/[email protected]
 0.8.1: git://github.com/docker/[email protected]
 0.9.1: git://github.com/docker/[email protected]
 
-2: git://github.com/docker/distribution-library-image@d5f65e019f029d7361be605b14180c93eddaf422
-2.1: git://github.com/docker/distribution-library-image@d5f65e019f029d7361be605b14180c93eddaf422
-2.1.1: git://github.com/docker/distribution-library-image@d5f65e019f029d7361be605b14180c93eddaf422
+2: git://github.com/docker/distribution-library-image@af287a2a6379ac099edc9c76672abe5cbe2f9469
+2.2: git://github.com/docker/distribution-library-image@af287a2a6379ac099edc9c76672abe5cbe2f9469
+2.2.0: git://github.com/docker/distribution-library-image@af287a2a6379ac099edc9c76672abe5cbe2f9469