[pitivi] undo: Remove duplicate signal

[Thibault Saunier <tsaunier src gnome org>]

commit ef8dc1fe22df5efb39e6aedc149e14ff35d9a061
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Fri Apr 11 19:14:53 2014 +0200

    undo: Remove duplicate signal

 pitivi/undo/undo.py |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)
---
diff --git a/pitivi/undo/undo.py b/pitivi/undo/undo.py
index 489ec47..2767015 100644
--- a/pitivi/undo/undo.py
+++ b/pitivi/undo/undo.py
@@ -46,7 +46,6 @@ class UndoableAction(Signallable):
     __signals__ = {
         "done": [],
         "undone": [],
-        "undone": [],
     }
 
     def do(self):