* Merge 4.8.2-2 from Debian testing to harmonize patches, and 4.8.2-3 from
  unstable for the small prerm fix, remaining Ubuntu changes:
  - debian/control: build-depends on libgconf2-dev and libgnome-keyring-dev
    to enable GNOME services support.
  - debian/rules: pass --enable-gnome --enable-libgnome-keyring to
    dh_auto_configure.
  - debian/patches:
    + xubuntu_lock-the-screen-on-hibernate-suspend.patch: copy the behavior
      of xfce4-power-manager for consistency.
    + xubuntu_ignore-gdm-lang.patch: do not set $LANG to $GDM_LANG, there's
      already an xsession script to do that, and $GDM_LANG might not contain
      a valid locale code.

* debian/xfce4-autostart-editor.1, debian/manpages: dropped, the binary
  doesn't exist on Xfce 4.6 and later. lp: #911688
* debian/patches:
  - 0001-Do-not-always-save-session-with-xfce4-logout-plugin-.patch: dropped,
    identical to 03_respect-save-settings-logout-plugin.patch.
  - xubuntu_lock-the-screen-on-hibernate-suspend.patch: updated to read the
    'lock-screen-suspend-hibernate' xfconf key from xfpm to avoid locking
    the screen on suspend/hibernate when the user disabled the feature.