[gcalctool] Update NEWS

[Robert Ancell <rancell src gnome org>]

commit f1a3ce6021a2b7592821a3255007474465d71a7f
Author: Robert Ancell <robert ancell canonical com>
Date:   Sun Oct 14 16:40:51 2012 +1300

    Update NEWS

 NEWS |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/NEWS b/NEWS
index fbbd8c2..d074eb8 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,10 @@
+Overview of changes in gcalctool 6.7.0
+
+    * Port to Vala
+    * Highlight parts of equation that have caused an error
+    * Fix error reporting not working for certain types of error
+    * Add shadow around display
+
 Overview of changes in gcalctool 6.6.0
 
     * Updated translations