Create one autosave per user
|Reported by:||azaozz||Owned by:||nacin|
Currently when autosaving drafts we overwrite them, when autosaving published posts, we keep one autosaved revision. This works well as long as there is only one post author.
Having per-user autosaves will affect only sites with many authors/editors. It will avoid overwriting when more than one user edits a post, provide better audit trail, and let us auto save data stored in the browser even if another user is editing at that moment.