Remove stale notification code

In this changeset, I cleaned up the Watcher codebase to remove
the old notification mechanism that is actually unused.

Partially Implements: blueprint watcher-notifications-ovo

Change-Id: I1901e65f031441b98a7d6f6c9c1c0364eaaaf481

watcher/tests/applier/test_rpcapi.py

@@ -27,14 +27,11 @@ from watcher.tests import base
 
 
 class TestApplierAPI(base.TestCase):
-    def setUp(self):
-        super(TestApplierAPI, self).setUp()
 
     api = rpcapi.ApplierAPI()
 
-    def test_get_version(self):
-        expected_version = self.api.API_VERSION
-        self.assertEqual(expected_version, self.api.get_version())
+    def setUp(self):
+        super(TestApplierAPI, self).setUp()
 
     def test_get_api_version(self):
         with mock.patch.object(om.RPCClient, 'call') as mock_call: