factory" (e.g. in the ``Router`` class) and ``webob.Response`` and
  the "response factory" (e.g. in ``render_template_to_response``),
  allow both to be overridden via a ZCML utility hook.  See the "Using
  ZCML Hooks" chapter of the documentation for more information.

- Remove old cold which attempts to recover from trying to unpickle a
  ``z3c.pt`` template; Chameleon has been the templating engine for a
  good long time now.  Running repoze.bfg against a sandbox that has
  pickled ``z3c.pt`` templates it will now just fail with an
  unpickling error, but can be fixed by deleting the template cache
  files.

  - Added a ``repoze.bfg.testing`` module to attempt to make it
    slightly easier to write unittest-based automated tests of BFG
    applications.  Information about this class is in the
    documentation.

  - The default template renderer now supports testing better by
    looking for ``ITestingTemplateRenderer`` using a relative
    pathname.  This is exposed indirectly through the API named
    ``registerTemplate`` in ``repoze.bfg.testing``.

  Deprecations

  - The names ``repoze.bfg.interfaces.ITemplate`` ,
    ``repoze.bfg.interfaces.ITemplateFactory`` and
    ``repoze.bfg.interfaces.INodeTemplate`` have been deprecated.
    These should now be imported as
    ``repoze.bfg.interfaces.ITemplateRenderer`` and
    ``repoze.bfg.interfaces.ITemplateRendererFactory``, and
    ``INodeTemplateRenderer`` respectively.

  - The name ``repoze.bfg.chameleon_zpt.ZPTTemplateFactory`` is
    deprecated.  Use ``repoze.bfg.chameleon_zpt.ZPTTemplateRenderer``.

  - The name ``repoze.bfg.chameleon_genshi.GenshiTemplateFactory`` is
    deprecated.  Use
    ``repoze.bfg.chameleon_genshi.GenshiTemplateRenderer``.

  - The name ``repoze.bfg.xslt.XSLTemplateFactory`` is deprecated.
    Use ``repoze.bfg.xslt.XSLTemplateRenderer``.