Add simple_linear_listening example to generated docs

This one is a nice to have in the examples, and should
also be updated to not use deprecated properties.

Change-Id: I5ee754525caccf0a9ea2a2b00aaa4e0d305e55b7

doc/source/examples.rst

@@ -34,6 +34,18 @@ Using listeners
     :linenos:
     :lines: 16-
 
+Using listeners (to watch a phone call)
+=======================================
+
+.. note::
+
+    Full source located at :example:`simple_linear_listening`.
+
+.. literalinclude:: ../../taskflow/examples/simple_linear_listening.py
+    :language: python
+    :linenos:
+    :lines: 16-
+
 Dumping a in-memory backend
 ===========================
 

taskflow/examples/simple_linear_listening.py

@@ -92,11 +92,11 @@ engine = taskflow.engines.load(flow, store={
 })
 
 # This is where we attach our callback functions to the 2 different
-# notification objects that an engine exposes. The usage of a '*' (kleene star)
+# notification objects that an engine exposes. The usage of a ANY (kleene star)
 # here means that we want to be notified on all state changes, if you want to
 # restrict to a specific state change, just register that instead.
 engine.notifier.register(ANY, flow_watch)
-engine.task_notifier.register(ANY, task_watch)
+engine.atom_notifier.register(ANY, task_watch)
 
 # And now run!
 engine.run()