Simplified job box sorting in GUI, now ignoring status except for finished and sorting from oldest to youngest. Finished still go at the bottom.  Some other misc code cleanup in gui.py.

Server now saves state immediately before shutting down, and writes a note to the log of any unfinished jobs in queue.  Autostart will now start paused jobs first regardless of age.

Simplified MarkedScale in tk_extensions to avoid the issue of scaling tick marks.  Now it's packed with a callback to update a number just above the scale.