post editing / deletion with edit history
Whenever a post is edited, the edited version is pushed out to timelines as if it were a new post, and takes the place of the previous post with the same post_id.
Also whenever a post is deleted a similar thing happens except the edited version of the post has content=None
or content=''
which when read by the front end doesn't produce an empty post, but instead doesn't display that post at all (unless you specifically request it)
ALSO there needs to be a relationship dependent visibility level on being able to see edit history