[gnome-session] (6 commits) Non-fast-forward update to branch wip/benzea/systemd-user-switch

[Benjamin Berg <bberg src gnome org>]

The branch 'wip/benzea/systemd-user-switch' 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:

  f346fc9... data: Add systemd user units
  8142fbe... main: Enable systemd usage
  41abc6c... manager: Drop DBus restart as it is handled using systemd
  87fd285... system: Remove is_last_session API as it is unused
  6f69bf5... main: Export autostart dir into environment

Commits added to the branch:

  ecca56e... data: Add systemd user units
  61b3966... manager: Quit session manager after completing shutdown
  261ebe5... main: Enable systemd usage
  6035b1a... manager: Drop DBus restart as it is handled using systemd
  416c1e2... system: Remove is_last_session API as it is unused
  f83fedc... main: Export autostart dir into environment