[Checkins] [zopefoundation/Zope] c36def: New branch to fix TAL default handling (#853)

[Jens Vagelpohl]

  Branch: refs/heads/4.x
  Home:   https://github.com/zopefoundation/Zope
  Commit: c36defd323a09c02b27ff71796c15a95c05cf9ee
      https://github.com/zopefoundation/Zope/commit/c36defd323a09c02b27ff71796c15a95c05cf9ee
  Author: Jens Vagelpohl <jens at netz.ooo>
  Date:   2020-06-26 (Fri, 26 Jun 2020)

  Changed paths:
    M constraints.txt
    M requirements-full.txt
    M src/Products/PageTemplates/engine.py
    A src/Products/PageTemplates/tests/input/BooleanAttributes.html
    M src/Products/PageTemplates/tests/input/Default.html
    A src/Products/PageTemplates/tests/output/BooleanAttributes.html
    M src/Products/PageTemplates/tests/output/Default.html
    M src/Products/PageTemplates/tests/testHTMLTests.py
    M versions-prod.cfg

  Log Message:
  -----------
  New branch to fix TAL default handling (#853)

* - new branch to fix TAL default handling

* adapt to changed default handling of `chameleon==3.7.4` (does not yet work

* Python 3 compatibility

* - use Chameleon 3.8

* Adaptations for `chameleon>=3.8`

* - fix lint issue

* - add test for straight boolean after seeing malthe/chameleon#318

* - comment change [ci skip]

Co-authored-by: dieter <dieter at handshake.de>