Update metadata for release 2.0.6

Change-Id: I45b47bc23b3ed2bb8cc85f09f5aae681c902a193
Reviewed-on: http://review.couchbase.org/26110
Tested-by: Sergey Avseyev <sergey.avseyev@gmail.com>
Reviewed-by: Matt Ingenthron <matt@couchbase.com>