[Checkins] [zopefoundation/Zope] d0274a: Fixes for Plone/Archetypes (#812)

[Dieter Maurer]

  Branch: refs/heads/4.x
  Home:   https://github.com/zopefoundation/Zope
  Commit: d0274a995541f5d6b1b7d2e6979a441b4a4c5ca5
      https://github.com/zopefoundation/Zope/commit/d0274a995541f5d6b1b7d2e6979a441b4a4c5ca5
  Author: Dieter Maurer <d-maurer at users.noreply.github.com>
  Date:   2020-03-31 (Tue, 31 Mar 2020)

  Changed paths:
    M CHANGES.rst
    M constraints.txt
    M requirements-full.txt
    M setup.py
    M src/Products/PageTemplates/engine.py
    M src/Products/PageTemplates/tests/input/InterpolationInContent.html
    A src/Products/PageTemplates/tests/input/PathAlternativesWithSpaces.html
    A src/Products/PageTemplates/tests/output/CH_PathAlternativesWithSpaces.html
    M src/Products/PageTemplates/tests/output/InterpolationInContent.html
    A src/Products/PageTemplates/tests/output/PathAlternativesWithSpaces.html
    A src/Products/PageTemplates/tests/testC2ZContext.py
    M src/Products/PageTemplates/tests/testHTMLTests.py
    M versions-prod.cfg

  Log Message:
  -----------
  Fixes for Plone/Archetypes (#812)

* Fixes for Plone/Archetypes

* update `constraints.txt`

* add `__iter__` to `_C2ZContextWrapper`