Update CHANGES and tox env
diff --git a/CHANGES b/CHANGES
index 35e9ba5..c142c6c 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,5 +1,6 @@
 + Version 2.15 (??.2016)
 
+  - PR #121: Update bundled PLY version to 3.8
   - Issue #117: Fix parsing of extra semi-colons inside structure declarations.
   - PR #109: Update c_generator to add {} around nested named initializers.
   - PR #101: Added support for parsing pragmas into the AST.