Reformat decl of new _PyString_Join.  Add NEWS blurb about repr() speedup.
diff --git a/Misc/NEWS b/Misc/NEWS
index 2bf6be4..bfbcc5f 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -126,6 +126,9 @@
   faster now.  Thanks to Christian Tismer for pointing out the cause and
   the nature of an effective cure (last December! better late than never).
 
+- repr() is much faster for large containers (dict, list, tuple).
+
+
 Library
 
 - A new function fnmatch.filter to filter lists of file names was added.