I redid this whole area from scratch in the new codebase. Let me know if my changes address your concerns. It allows deletion of files, revision histories, lists what pages link to which images (the database is a bit out-of date on that--but the features work in the software). Currently it warns about, but does not restrict, the uploading of files other than PNG, JPEG, and GIF. I can easily be talked into eliminating GIF from that list and adding OGG, and we might want to add a feature for being able to include sounds, especially for things like pronunciations of words.
As always, I welcome bug reports and suggestions.
http://www.piclab.com/newwiki/wiki.phtml
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