Exit cleanly on keyboard interrupt

itm-decode.py

@@ -162,7 +162,11 @@ def main(argv):
                 yield None
             else:
                 yield data[0]
-    ITMParser(input_stream()).process()
+
+    try:
+        ITMParser(input_stream()).process()
+    except KeyboardInterrupt:
+        raise SystemExit(0)
 
 if __name__ == "__main__":
     main(sys.argv)