Merge branch 'master' into extensionlist-listener

* master:
  Noting merge of JENKINS-28111
  @jglick wants it this way
  Noting merge of JENKINS-28115
  [FIXED JENKINS-28115] Division by zero in Executor.getProgress()
  [FIXED JENKINS-28111] JNLP slave JVM Options are inconsistently applied
  updated changelog for release
  [maven-release-plugin] prepare for next development iteration
  [maven-release-plugin] prepare release jenkins-1.611
  remove ips profile
  Now that packaging is in https://github.com/jenkinsci/packaging and given that the ips packaging is stale, we should just drop this