Wrap long lines in CHANGES. (#61)

diff --git a/CHANGES b/CHANGES
index f7d411c..2fc003f 100644
--- a/CHANGES
+++ b/CHANGES
@@ -8,10 +8,11 @@
 3.1.1
 =====
 
-- Backported sanity checks for the ``max_workers`` constructor argument for ThreadPoolExecutor and
-  ProcessPoolExecutor
-- Set the default value of ``max_workers`` in ThreadPoolExecutor to ``None``, as in upstream code
-  (computes the thread pool size based on the number of CPUs)
+- Backported sanity checks for the ``max_workers`` constructor argument for
+  ThreadPoolExecutor and ProcessPoolExecutor
+- Set the default value of ``max_workers`` in ThreadPoolExecutor to ``None``,
+  as in upstream code (computes the thread pool size based on the number of
+  CPUs)
 - Added support for old-style exception objects
 - Switched to the PSF license
 
@@ -25,7 +26,8 @@
 3.0.5
 =====
 
-- Fixed OverflowError with ProcessPoolExecutor on Windows (regression introduced in 3.0.4)
+- Fixed OverflowError with ProcessPoolExecutor on Windows (regression
+  introduced in 3.0.4)
 
 
 3.0.4