[Checkins] [zopefoundation/Zope] 71da5d: Better session documentation and link (#885)

[Jens Vagelpohl]

  Branch: refs/heads/4.x
  Home:   https://github.com/zopefoundation/Zope
  Commit: 71da5d403c21f7e6ea208327e1ce627708950875
      https://github.com/zopefoundation/Zope/commit/71da5d403c21f7e6ea208327e1ce627708950875
  Author: Jens Vagelpohl <jens at netz.ooo>
  Date:   2020-08-21 (Fri, 21 Aug 2020)

  Changed paths:
    M docs/zope4/migration/removed.rst

  Log Message:
  -----------
  Better session documentation and link (#885)

* Better session documentation and link

Update seasoning documentation hint and link the chapter on sessions

* - clean up and expand

Co-authored-by: Jens Vagelpohl <jens at netz.ooo>