[gtkmm] Fix typo.

[Murray Cumming <murrayc src gnome org>]

commit cb924c61f9849f45e9bc5209ebac93ca531209e9
Author: Murray Cumming <murrayc murrayc com>
Date:   Wed Apr 6 16:04:00 2011 +0200

    Fix typo.

 NEWS |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/NEWS b/NEWS
index b65d8d6..6fcb52e 100644
--- a/NEWS
+++ b/NEWS
@@ -47,7 +47,7 @@ General:
   the explicit keyword here instead, but that is not yet widespread.
 * Many existing classes have many new methods.
 * gtkmm-3.0 currently has no deprecated API.
-  Note even API that was added and then deprecated during GTK+ 3.0.
+  Not even API that was added and then deprecated during GTK+ 3.0.
 
 
 3.0.0 (unstable):