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/decision_engine/messaging/events.py

@@ -1,26 +0,0 @@
-# -*- encoding: utf-8 -*-
-# Copyright (c) 2015 b<>com
-#
-# Authors: Jean-Emile DARTOIS <jean-emile.dartois@b-com.com>
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-# http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
-# implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-#
-
-import enum
-
-
-class Events(enum.Enum):
-    ALL = '*',
-    ACTION_PLAN = "action_plan"
-    TRIGGER_AUDIT = "trigger_audit"