VOL-1460:  Include voltha-protos in vendor

This forces voltha-protos to be like any other dependancy.
Keeping in line with checking in all vendor items.

Care must still be taken such that any other user of proto
doesnt cause these to break.  dep ensure would be needed to update.

Update gitignore to screen out items dep's prune brought over
that we didnt actually need.

Change-Id: If3ed03985ce9c73475ea1448af7aef848a8993a1
diff --git a/vendor/github.com/opencord/voltha-protos/.gitignore b/vendor/github.com/opencord/voltha-protos/.gitignore
new file mode 100644
index 0000000..9713c4f
--- /dev/null
+++ b/vendor/github.com/opencord/voltha-protos/.gitignore
@@ -0,0 +1,18 @@
+# python related
+*.pyc
+*.egg-info
+dist
+build
+.tox
+venv_protos
+
+# generated files that shouldn't be committed
+*_pb2.py
+*_pb2_grpc.py
+*.desc
+
+# tesing related
+.coverage
+*coverage.xml
+*results.xml
+