We run by default with a panel (default gnome-panel) and then run Openbox
without any panel if one cannot be found.

- Adds a fallback session for if a panel (default gnome-panel) not found.
- Removes notifications as a requirement.  Seems to be a legacy thing judging
  from the ubuntu .session files.  Notifications are being provided by
  notify-osd on modern systems, and you can't check for its presence in
  gnome-session (gnome-classic.session always fails because it looks for it, so
  ubuntu falls back to gnome-fallback.session).

Yay they did something nice and made it easier for other window managers to be used.  How unexpected and pleasant.

Startup scripts should export "XDG_MENU_PREFIX=kde-4-" but they export
"XDG_MENU_PREFIX=kde-".

add /usr/libexec/openbox-autostart which runs the global/user scripts and
  launches /usr/libexec/openbox-xdg-autostart (which runs .desktop autostart
  stuff)

make openbox-session call openbox with --startup option, to make openbox launch
  /usr/libexec/openbox-autostart *after* it is initialized.

add /etc/xdg/openbox/environment and ~/.config/openbox/environment files to let
  user change environment variables (locale) for their Openbox session, which
  openbox-session loads before running openbox.

Conflicts:

	openbox/frame.c

Conflicts:

	Makefile.am
	openbox/actions/focus.c
	openbox/config.c
	openbox/event.c
	openbox/menuframe.c