[gdm] (16 commits) Non-fast-forward update to branch wip/wayland-rebase

[Jasper St. Pierre <jstpierre src gnome org>]

The branch 'wip/wayland-rebase' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  0a7b2e7... worker: move PAM tty/display setup to open session
  4ca6ae1... daemon: add new gdm_session_is_running method
  db326a1... daemon: move user session code from slave to main daemon
  72b4613... Integrate the slaves into the main daemon process
  f35df90... slave: add ability to reset launch environment
  59b947c... session: Prevent memory leaks by removing strdup accessors
  ff217f2... manager: Change code that activates / unlocks sessions to t
  e592edf... manager: Add infrastructure to hand-over Wayland session
  f4c675d... Add wayland-sessions
  374c3ac... own display server

Commits added to the branch:

  2d02525... Fix build problem on FreeBSD (*)
  9539d07... slave: Add back setting of session-id (*)
  6d96281... slave: Remove unused variable (*)
  24677dc... Revert "move over to using 'dconf compile' and file-db"
  0ed7ebb... server: Properly set the DISPLAY envvar
  a16aa53... server: Remove unused properties
  f6688c3... worker: move PAM tty/display setup to open session
  784e510... daemon: add new gdm_session_is_running method
  16465a1... daemon: move user session code from slave to main daemon
  2470c63... Integrate the slaves into the main daemon process
  b5a9b95... slave: add ability to reset launch environment
  6d521bb... session: Prevent memory leaks by removing strdup accessors
  ebb0274... manager: Reset our own greeter when in a Wayland session
  baaab33... Add wayland-sessions
  b7094a2... own display server
  f927077... ff

(*) This commit already existed in another branch; no separate mail sent