- more explicit compatibility documentation

README.md

@@ -1,7 +1,13 @@
 Products.ZMySQLDA
 =================
-This is the MySQL database adapter product for Zope
-versions 2.13 and up as well as Zope 4.
+This is the MySQL database adapter product for Zope.
 
-The ZMySQLDA database adapter is compatible with MySQL versions 3.22 and
-later. You need version 4.1 or higher for unicode support.
+Compatibility
+-------------
+* ``Zope2`` 2.13.26 and up under Python 2.7 in conjunction with
+  ``Products.ZSQLMethods`` up to and including 2.13.5.
+
+* ``Zope`` 4 after 4.0beta5 under either Python 2.7, 3.5 or 3.6.
+
+* MySQL versions 3.22 and later including MariaDB. You need version 4.1
+  or higher for unicode support.