----------------
- Add support for ``Products.ZCatalog >= 4`` while dropping support for older
versions. [icemac, 2018-07-11]
- Add support for Python 3.5 and Python 3.6 on Zope 4. While dropping support
for older Zope versions. [icemac, 2018-07-11]
- Remove dependency from `Globals` for Zope 4 compat. [sallner, 2017-08-21]
- some code cleanup [jensens, 2016-06-14]