Manage Attachments History (allow to delete attachments revision)

Following a forum discussion(1), I suggest to have a screen to manage attachment history  like we can manage page history. This screen should:

• list all available revisions for an attachment (like today)
• allow to download / view a particular revision of the attachment (like today)
• allow to delete an attachment revision (new feature).

Option: when deleting an attachment revision, XWiki could inform the user which page(s) revision are "using" the revision of the attachment.

(1) see forum thread: https://forum.xwiki.org/t/delete-old-attachments/5049