Add Event Sources:

- Add source property in Action and EventFilter
- Change TPropContainer contructor to accept keyword arguments and set
  properties that were given
- Change every single TPropContainer subclass constructor to accept
  kwargs and pass them on to super init
- Add a "null" option for TStringProperty
Use Event Sources:
- Make the probe require a source property to install or subscribe
- Have ProbeProxy install and subscribe return a prefixed address
- Make update, uninstall and unsubsribe extract the prefix from the
  address
- Have the TutorialRunner set a source on actions/events before
  installing/subscribing instead of setting current activity on
  ProbeManager
Test Event Sources:
- Change the tests according to the new constructors and behaviors

1 files changed, 3 insertions, 4 deletions

diff --git a/addons/disablewidget.py b/addons/disablewidget.py
index 8b34254..15e07f2 100644
--- a/addons/disablewidget.py
+++ b/addons/disablewidget.py
@@ -21,13 +21,12 @@ from ..services import ObjectStore
 class DisableWidgetAction(Action):
     target = TStringProperty("0")
 
-    def __init__(self, target):
+    def __init__(self, **kwargs):
         """Constructor
+        Accepted keyword args:
         @param target target treeish
         """
-        Action.__init__(self)
-        if target is not None:
-            self.target = target
+        super(DisableWidgetAction, self).__init__(**kwargs)
         self._widget = None
 
     def do(self, **kwargs):