Fix: don't forgot button border width when wrapping text.

diff --git a/qwerty.py b/qwerty.py
index b887612..9c967ef 100755
--- a/qwerty.py
+++ b/qwerty.py
@@ -92,7 +92,7 @@ class SuperButton(gtk.DrawingArea):
                 s = s + ' ' + word
             else:
                 s = word
-            if size(s) >= self.width - LABEL_LEFT - PADDING:
+            if size(s) >= self.width - LABEL_LEFT - PADDING-2:
                 lines.append(old)
                 s = word
             else: