------------------
- Remove test dependencies on zope.app.testing, zope.app.zcmlfiles,
and others.
- Remove install dependency on zope.app.form, replaced with direct
imports of zope.formlib.
- Simplify ``zope.app.component.testing`` to remove the deprecated or
broken functionality in ``testingNextUtility`` and
``SiteManagerStub``. ``PlacefulSetup`` is retained (and incorporates
much of what was previously inherited from ``zope.app.testing``),
although use of ``zope.component.testing.PlacelessSetup`` is
suggested when possible.
- Add support for PyPy and Python 3.4, 3.5 and 3.6.