Log Message:
Import Jenkins 2.19.1 (LTS) as devel/jenkins-lts.

Changes since 2.7.4 (last LTS update made under devel/jenkins):

Changes from 2.19:
- Fixed the missing icon in the System Script console.
- Fixed background color in the ComboBoxList element in order to
  make options visible.
- Fixed editing default view description with automatic refresh.
  System message is not being displayed instead of the view
  description.
- Do not process null CRON specifications in build triggers.
- Setup wizard now checks if the restart is supported on the
  system before displaying the restart button.
- Test Windows junctions before Java 7 symlink in symbolic link
  checks.

Notable changes since 2.7.4:
- Fix plugin dependency resolution. Jenkins will now refuse to
  load plugins with unsatisfied dependencies, which resulted in
  difficult to diagnose problems. This may result in errors on
  startup if your instance has an invalid plugin configuration.,
  check the Jenkins log for details.
- Don't load all builds to display the paginated build history
  widget.
- Tell browsers not to cache or try to autocomplete forms in
  Jenkins to prevent problems due to invalid data in form
  submissions. From now on, only select form fields (e.g. job name)
  will offer autocompletion.
- Add diagnostic HTTP response to TCP agent listener.
- Allow admins to control the enabled agent protocols on their
  instance from the global security settings screen.
- Prevent NullPointerException on startup after update from
  Jenkins 2.5.
- Always send usage statistics over HTTPs to the new
  usage.jenkins.io hostname.
- Do not inject build variables into Maven process by default for
  new projects.
- IllegalStateException under certain conditions when reloading
  configuration from disk while jobs are in the queue.
- Underprivileged users were unable to use the default value of a
  password parameter.