speedup extension is now disabled by default (added message) and fixed a
line in the docs.

--HG--
branch : trunk
diff --git a/CHANGES b/CHANGES
index c4f9b3f..05d28d7 100644
--- a/CHANGES
+++ b/CHANGES
@@ -23,6 +23,7 @@
 - Added the `meta` module.
 - Renamed (undocumented) attribute "overlay" to "overlayed" on the
   environment because it was clashing with a method of the same name.
+- speedup extension is now disabled by default.
 
 Version 2.1.1
 -------------