Specifies the background image for Webulator/400. This will be sent as an
attribute of the BODY tag and is an extension to HTML 2.0. Being an
extension, be aware it may not be supported by all browsers.
The URL of the image file to load. This must contain a leading slash ('/')
to make it relative to the document root.
If no Image is specified, none will be loaded by the browser.
Default if no entry found
If no entry is provided for a directory, the parent directory's value will be
inherited. If the root directory has no entry, the default, which is to
not use a background image,
will be inherited.