Issue 6877: this patch makes it possible to link the readline extension
to the libedit emulation of the readline API on OSX 10.5 or later.

This also adds a minimal testsuite for readline to check that the
history manipuation functions have the same interface with both
C libraries.
diff --git a/Misc/NEWS b/Misc/NEWS
index bdd121c..8261b6c 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -1335,6 +1335,9 @@
 Extension Modules
 -----------------
 
+- Issue #6877: Make it possible to link the readline extension to libedit
+  on OSX.
+
 - Issue #6944: Fix a SystemError when socket.getnameinfo() was called
   with something other than a tuple as first argument.