CHANGES.md: Replace "Next Release" with "1.5.7"

jcfr · jcfr · commit 31749c473a8c · 2017-11-08T18:44:19.000-05:00
[ci skip]
diff --git a/CHANGES.md b/CHANGES.md
@@ -1,5 +1,5 @@
-Next Release
-============
+1.5.7
+=====
 
 Features (CLI and Python API)
 -----------------------------
