Improve Rich editor to allow to Insert/Edit Link to attachments in different pages and spaces, not just the current page.

Enable linking to attachments in different spaces and pages using the "link" icon in Editor toolbar.

Presently, an user can use the Insert/Edit link to link to attachments attached to the current page only.

Please see associated discussion here:

http://forums.atlassian.com/thread.jspa?forumID=96&threadID=12007

"Unfortunately, I'm in a situation where most of our users will simply not refer to the attachment at all rather than learn the notation for adding the attachment in wiki; in other words, if they can't do it in the GUI, they won't do it at all."

"What I'd like is when I do a search, or i go to the Recently modified tab, that attachments also show up, regardless of space or parent. "