VOL-1097 : Ofagent integration for voltha 2.0

- Created a common location for python based components
- Adjusted the ofagent component to interact with voltha 2.0
- Added streaming rpc methods for rcv/send of packets to voltha api
- Adjusted voltha.proto

Change-Id: I47fb7b80878ead060b4b42bd16cb4f8aa384fdb6
diff --git a/python/docker/Dockerfile.ofagent b/python/docker/Dockerfile.ofagent
new file mode 100644
index 0000000..48b4728
--- /dev/null
+++ b/python/docker/Dockerfile.ofagent
@@ -0,0 +1,45 @@
+# 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-base:${TAG}
+
+MAINTAINER Voltha Community <info@opennetworking.org>
+
+# Install protoc version 3.0.0; this is not yet the supported
+# version on xenial, so we need to "backport" it
+RUN apt-get update && \
+    apt-get install -y zlib1g-dev wget && \
+    wget http://ftp.us.debian.org/debian/pool/main/p/protobuf/libprotoc10_3.0.0-9_amd64.deb && \
+    wget http://ftp.us.debian.org/debian/pool/main/p/protobuf/libprotobuf-lite10_3.0.0-9_amd64.deb && \
+    wget http://ftp.us.debian.org/debian/pool/main/p/protobuf/libprotobuf-dev_3.0.0-9_amd64.deb && \
+    wget http://ftp.us.debian.org/debian/pool/main/p/protobuf/libprotobuf10_3.0.0-9_amd64.deb && \
+    wget http://ftp.us.debian.org/debian/pool/main/p/protobuf/protobuf-compiler_3.0.0-9_amd64.deb && \
+    dpkg -i *.deb && \
+    protoc --version && \
+    rm -f *.deb
+
+# Bundle app source
+RUN mkdir /ofagent && touch /ofagent/__init__.py
+ENV PYTHONPATH=/ofagent
+COPY common /ofagent/common
+COPY ofagent /ofagent/ofagent
+COPY pki /ofagent/pki
+
+ENTRYPOINT ["/usr/bin/dumb-init", "--"]
+
+# Exposing process and default entry point
+CMD ["dumb-init", "python", "ofagent/ofagent/main.py"]