Add show/hide capability to attached files, images, and comments

It would be nice to be able to hide the attached comments, files, and images at the bottom of each wiki page.

In my experience, this would be especially useful for the attached images. They're *usually* embedded in the wiki page, so you end up seeing them twice. I find it distracting. Ideally, make the default (shown or hidden) selectable in the control panel. For extra credit, make it overridable by each user's preferences.