$abs_svc_uri patch

Replaced certain hard-coded instances of "http://validator.w3.org" with
reference to ${abs_svc_uri}, to permit offline/alternate versions of the
Validator to pull images from the local copy (rather than directly from
validator.w3.org or www.w3.org).  Added $loc_svc_uri, $loc_image_uri
variables to help.

I would call it more of a "courtesy" patch -- if you're going to make your
own copy of the validator accessible, serve the images from your own server!

Brian

>  Brian Gilkison           | http://w3.one.net/~gilkison/ <
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