Fix for bug 300949: reverts fix for bug 274906 which eliminated [edit] link next...

Fix for bug 300949: reverts fix for bug 274906 which eliminated [edit] link next to attachments to avoid duplicate [edit] references and made the main attachment link go to the 'edit attachment' page; that fix unreasonably reduced Bugzilla usability by making it difficult to view attachments; this patch includes a different fix for bug 274906 that prevents those duplicate [edit] references; long-term we want to make the 'edit attachment' page the irresistable default and have a pop-up menu of links, at which point [edit] can truly go away, but for now it stays