Bug 572388 - Link javadocs against against OSGi R8 javadocs While at it fix version to say 2021-06 (4.20) and copyright year to be 2021. This hasn't been changed for the last 2 releases. Change-Id: I94a5aafb2328e21f9ac3a45dbaf8ec2878d20217 Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>