[release] pkgdb2: 2.6

Good Morning Everyone, I just cut a new pkgdb2 release: 2.6. Here is the corresponding changelog: * Wed Jan 18 2017 Pierre-Yves Chibon <pingou(a)pingoured.fr&gt; - 2.6-1 - Update to 2.6 - Fix bug in splitting the title of bug reports (Patrick Uiterwijk) - Add a link to koschei from the package page (Vít Ondruch) - Do not require a review_url when asking to unretire master - Fix approving a new package request in the docker namespace - Fix sending notifications when we update the status of a package on a branch This is currently happily running in stg, so feel free to poke at it if you want to test it more. (Note the fix for new package request in docker namespace has been applied in prod when created) I want to release a new pkgdb-cli before pushing this release to production, so it won't hit prod before a day or two. Happy packaging, Pierre