VOL-1500 VOL-1475 Updated the remaining python containers in voltha-go to use pyvoltha and voltha-protos

Changed the build system to have separate flags for local pyvoltha and local protos.
Cleared out now unneeded python libraries and protos from voltha-go

PonSim was tested by launching the system-test-ponsim.yml and making sure the ponsim enables.
This was tested on docker-compose and k8s.
Let me know if there are other cases to test.

Change-Id: Ie2d5a19900fcfc93b96aba2981efb18fd9e649bb
diff --git a/python/ofagent/converter.py b/python/ofagent/converter.py
index 192a65a..d3c7bea 100755
--- a/python/ofagent/converter.py
+++ b/python/ofagent/converter.py
@@ -23,7 +23,7 @@
 
 import loxi.of13 as of13
 from protobuf_to_dict import protobuf_to_dict, TYPE_CALLABLE_MAP
-from protos import openflow_13_pb2 as pb2
+from voltha_protos import openflow_13_pb2 as pb2
 
 
 type_callable_map = copy(TYPE_CALLABLE_MAP)