Smart Backgrounds support

[gjh42]

What image names do you have, and where are they saved?
You do want a base image named (in this case) smartimg.jpg, for display when there is no specific image matching a page. If there is no match, the function will return null, and the base name and extension will be used.

There is no template override available in /includes/functions/, so
/includes/functions/extra_functions/smart_backgrounds_functions.php as the readme describes is correct. The zip has the extra folder. I have corrected this and reposted the zip.