horizon 16.0.0.0rc2 release candidate

meta:version: 16.0.0.0rc2
meta:diff-start: -
meta:series: train
meta:release-type: release candidate
meta:pypi: no
meta:first: no
meta:release:Author: Ivan Kolodyazhny <e0ne@e0ne.info>
meta:release:Commit: Ivan Kolodyazhny <e0ne@e0ne.info>
meta:release:Change-Id: I61b927c3a5540205b2697545cb0104abec00b67a
meta:release:Code-Review+1: Akihiro Motoki <amotoki@gmail.com>
meta:release:Code-Review+2: Thierry Carrez <thierry@openstack.org>
meta:release:Code-Review+2: Sean McGinnis <sean.mcginnis@gmail.com>
meta:release:Workflow+1: Sean McGinnis <sean.mcginnis@gmail.com>