Use Zope 2.13.9 .
Drop python2.6 .

Use 2.7 instead.
version up : Zope 2.13.18.
Merge remote-tracking branch 'origin/erp5-component' into erp5-component-z2.13
Temporarily keep zope.app.testing for tests like testCookieCrumbler
Merge branch 'erp5-component' into erp5-component-z2.13

Conflicts:
	stack/erp5/buildout.cfg
version up: Zope2 2.13.19
Merge erp5-component-z2.13 into erp5-cluster-z2.13

Conflicts:
	stack/erp5/buildout.cfg
Hack to use correct branch