Initial commit moving openolt adapter from voltha-go to the new repo.
This version works with ponsim rather than openolt, this is temporary.
It is currently being fixed to work with openolt.

Change-Id: I34a800c98f050140b367e2d474b7aa8b79f34b9a
Signed-off-by: William Kurkian <wkurkian@cisco.com>
diff --git a/python/common/utils/registry.py b/python/common/utils/registry.py
new file mode 100644
index 0000000..270bd71
--- /dev/null
+++ b/python/common/utils/registry.py
@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+#
+# Copyright 2017 the original author or authors.
+#
+# 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.
+#
+
+"""
+Simple component registry to provide centralized access to any registered
+components.
+"""
+from collections import OrderedDict
+from zope.interface import Interface
+
+
+class IComponent(Interface):
+    """
+    A Voltha Component
+    """
+
+    def start():
+        """
+        Called once the componet is instantiated. Can be used for async
+        initialization.
+        :return: (None or Deferred)
+        """
+
+    def stop():
+        """
+        Called once before the component is unloaded. Can be used for async
+        cleanup operations.
+        :return: (None or Deferred)
+        """
+
+
+class Registry(object):
+
+    def __init__(self):
+        self.components = OrderedDict()
+
+    def register(self, name, component):
+        assert IComponent.providedBy(component)
+        assert name not in self.components
+        self.components[name] = component
+        return component
+
+    def unregister(self, name):
+        if name in self.components:
+            del self.components[name]
+
+    def __call__(self, name):
+        return self.components[name]
+
+    def iterate(self):
+        return self.components.values()
+
+
+# public shared registry
+registry = Registry()