python-ironicclient 2.6.0 release

meta:version: 2.6.0
meta:diff-start: -
meta:series: stein
meta:release-type: release
meta:pypi: yes
meta:first: yes
meta:release:Author: Sean McGinnis <sean.mcginnis@gmail.com>
meta:release:Commit: Sean McGinnis <sean.mcginnis@gmail.com>
meta:release:Change-Id: I91db6a4ac40d25dd29f2176e5f0a56f44e93a7ca
meta:release:Code-Review+1: Dmitry Tantsur <divius.inside@gmail.com>
meta:release:Code-Review+1: Julia Kreger <juliaashleykreger@gmail.com>
meta:release:Code-Review+2: Doug Hellmann <doug@doughellmann.com>
meta:release:Code-Review+1: Jean-Philippe Evrard <jean-philippe@evrard.me>
meta:release:Code-Review+2: Tony Breeds <tony@bakeyournoodle.com>
meta:release:Workflow+1: Tony Breeds <tony@bakeyournoodle.com>