Add a tox test runner.

The py27-pure environment fails as expected while trying to use the
not-yet optional AccessControl C extension.

.gitignore

@@ -2,6 +2,7 @@
 *.py?
 .installed.cfg
 .mr.developer.cfg
+.tox
 /bin/
 /build/
 /develop/

buildout.cfg

@@ -33,7 +33,9 @@ eggs = Zope2
 
 [zopescripts]
 recipe = zc.recipe.egg
-eggs = Zope2
+eggs =
+    Zope2
+    tox
 
 
 [zserverscripts]

tox.ini

+[tox]
+envlist =
+   py27,py27-pure
+
+[testenv]
+install_command = pip install --no-cache-dir --no-binary=:all: {opts} {packages}
+commands =
+    zope-testrunner --test-path={envsitepackagesdir} -s Zope2
+deps =
+    zope.testrunner
+setenv =
+    PIP_NO_CACHE = 1
+
+[testenv:py27-pure]
+basepython =
+    python2.7
+setenv =
+    PURE_PYTHON = 1

versions.cfg

@@ -20,6 +20,8 @@ MarkupSafe = 0.23
 mr.developer = 1.34
 nose = 1.3.7
 plone.recipe.command = 1.1
+pluggy = 0.4.0
+py = 1.4.32
 Pygments = 2.1.3
 python-gettext = 3.0
 python-subunit = 1.2.0
@@ -27,7 +29,9 @@ setuptools = 28.6.1
 snowballstemmer = 1.2.1
 Sphinx = 1.4.8
 testtools = 2.2.0
+tox = 2.5.0
 unittest2 = 1.1.0
+virtualenv = 15.1.0
 z3c.checkversions = 0.5
 zc.buildout = 2.5.3
 zc.recipe.egg = 2.0.3