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- Depend on and use the new features of the zc.buildout 1.5 line. At the same
time support for zc.buildout <= 1.5.1 has been dropped.
- Fixed test setup to run with current zopetoolkit packages.
Made sure tests still run on older platforms, particularly Zope 2.12.
- Using python's `doctest` module instead of deprecated
`zope.testing.doctest`.
- Typo change in configuration: exludeDirNames becomes excludeDirNames (old
name is still supported for backward compatibility).