Zope.traversing

==================

- Move ``IBeforeTraverseEvent`` here from ``zope.app.publication``,
as we already deal with publication traversal.

==================

- In ``zope.traversing.api.getParent()``, try to delegate to
``zope.location.interfaces.ILocationInfo.getParent()``, analogous to
``getParents()``. Keep returning the traversal parent as a fallback.

- Bring ``ITraverser`` back from ``zope.location`` where it had been moved
to invert the package interdependency, but where it is now no longer used.

==================

- Make virtual hosting tests compatible with ``zope.publisher`` 3.9.
Redirecting to a different host requires an explicit ``trusted``
redirect now.

==================

- ``AbsoluteURL`` now implements the fact that ``__call__`` returns the same
as ``__str__`` in a manner that it applies for subclasses, too, so they only
have to override ``__str__`` and not both.

==================

- Move the ``publicationtraverse`` module to ``zope.traversing``, removing the
``zope.app.publisher`` -> ``zope.app.publication`` dependency (which was a
cycle).

- Look up the application controller through a utility registration
rather than a direct reference.

==================

- Change ``configure.zcml`` not to depend on ``zope.app.component``.

- This release includes the BBB-incompatible ``zope.publisher.skinnable``
change from 3.5.3.