* Deal better with rebuilds that involve moving files; track and clean up the

* Deal better with rebuilds that involve moving files; track and clean up the
  old files.
* Change where the img plugin puts scaled images. It's better to make the
  scaled images subpages of the page that embeds them, rather than putting
  them alongside the original image, since if two pages scale the same image
  the same way, this prevents complications in dealing with two pages
  creating the same file. The move will be handled transparently, though you
  might want to rebuild your wiki to make it occur in one step.