New methods, Item.renameAttachmentFile(newName, force) -- _force_ forces overwrite of an existing file
For the moment, implemented in the UI via a checkbox in the attachment title rename dialog (accessible by clicking on the title in the right pane) to rename the associated file as well -- this might be replaced by the upcoming keep-filenames-in-sync-with-attachment-titles feature, but it's probably fine for Beta 3.
Also new:
- Zotero.Attachments.getPath(file, linkMode) to get a relative or persistent path as appropriate given the link mode