Revert c109400 (ExtensionClass getstate) on the stable branch, until...

Revert c109400 (ExtensionClass getstate) on the stable branch, until http://dev.plone.org/plone/ticket/10318 has been fixed

doc/CHANGES.rst

@@ -13,9 +13,9 @@ Features Added
 
 - Updated packages:
 
-  - Acquisition = 2.13.1
-  - ExtensionClass = 2.13.0
-  - Persistence = 2.13.0
+  - Acquisition = 2.13.0
+  - ExtensionClass = 2.12.0
+  - Persistence = 2.12.0
 
 - There is now an event ZPublisher.interfaces.IPubBeforeStreaming which will
   be fired just before the first chunk of data is written to the response

versions.cfg

@@ -2,15 +2,15 @@
 versions = versions
 
 [versions]
-Acquisition = 2.13.1
+Acquisition = 2.13.0
 ClientForm = 0.2.10
 DateTime = 2.12.0
 docutils = 0.6
-ExtensionClass = 2.13.0
+ExtensionClass = 2.12.0
 five.formlib = 1.0.2
 lxml = 2.2
 mechanize = 0.1.11
-Persistence = 2.13.0
+Persistence = 2.12.0
 python-gettext = 1.0
 pytz = 2009r
 RestrictedPython = 3.5.1