VOL-1460 Updated core to use voltha-protos instead of local protos
Moved protos to python directory in order to maintain functionaly of containers built there.
Added capability to do local builds of protos
Added instructions on running dep ensure for getting protos.
Updated github.com/golang/protobuf version to v1.3.1

Change-Id: Ia6ef55f07f0d5dcb5b750d7c37b21b71db85bfc4
diff --git a/vendor/github.com/golang/protobuf/proto/pointer_reflect.go b/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
index b6cad90..94fa919 100644
--- a/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
+++ b/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
@@ -79,10 +79,13 @@
 
 // toAddrPointer converts an interface to a pointer that points to
 // the interface data.
-func toAddrPointer(i *interface{}, isptr bool) pointer {
+func toAddrPointer(i *interface{}, isptr, deref bool) pointer {
 	v := reflect.ValueOf(*i)
 	u := reflect.New(v.Type())
 	u.Elem().Set(v)
+	if deref {
+		u = u.Elem()
+	}
 	return pointer{v: u}
 }