Make the Pynche tool work with Python 3.
diff --git a/Tools/pynche/ChipViewer.py b/Tools/pynche/ChipViewer.py
index f59aa28..78139f8 100644
--- a/Tools/pynche/ChipViewer.py
+++ b/Tools/pynche/ChipViewer.py
@@ -13,7 +13,7 @@
 selected and nearest ChipWidgets.
 """
 
-from Tkinter import *
+from tkinter import *
 import ColorDB