VOL-1449 Modify build environment to use pyvoltha

Depending on if LOCAL_PYVOLTHA is set use a build of
the library from the nearby source tree, for both
virtualenv and docker image builds.  By default
requirements.txt uses the pip hosted dev build, which
may not be new enough for iterative development

Also by setting PYVOLTHA_BASE_IMAGE use a docker image produced
by pyvoltha as the base image.

Change-Id: Ibf7218b92450f92d6a3f1c9d837be46fcc3a84db
diff --git a/python/docker/Dockerfile.openonu_adapter b/python/docker/Dockerfile.openonu_adapter
new file mode 100644
index 0000000..50251f1
--- /dev/null
+++ b/python/docker/Dockerfile.openonu_adapter
@@ -0,0 +1,31 @@
+# Copyright 2016 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.
+ARG TAG=latest
+ARG REGISTRY=
+ARG REPOSITORY=
+
+FROM ${REGISTRY}${REPOSITORY}voltha-openonu-adapter-base:${TAG}
+
+MAINTAINER Voltha Community <info@opennetworking.org>
+
+# Bundle app source
+RUN mkdir /voltha && touch /voltha/__init__.py
+RUN mkdir /voltha/voltha && touch /voltha/voltha/__init__.py
+RUN mkdir /voltha/voltha/adapters && touch /voltha/voltha/adapters/__init__.py
+ENV PYTHONPATH=/voltha
+COPY adapters/brcm_openomci_onu /voltha/voltha/adapters/brcm_openomci_onu
+
+# Exposing process and default entry point
+CMD ["python", "/voltha/python/adapters/openonu/main.py"]
+