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/Shopify/sarama/errors.go b/vendor/github.com/Shopify/sarama/errors.go
index c11421d..87a4c61 100644
--- a/vendor/github.com/Shopify/sarama/errors.go
+++ b/vendor/github.com/Shopify/sarama/errors.go
@@ -157,6 +157,10 @@
 	ErrFetchSessionIDNotFound             KError = 70
 	ErrInvalidFetchSessionEpoch           KError = 71
 	ErrListenerNotFound                   KError = 72
+	ErrTopicDeletionDisabled              KError = 73
+	ErrFencedLeaderEpoch                  KError = 74
+	ErrUnknownLeaderEpoch                 KError = 75
+	ErrUnsupportedCompressionType         KError = 76
 )
 
 func (err KError) Error() string {
@@ -311,6 +315,14 @@
 		return "kafka server: The fetch session epoch is invalid."
 	case ErrListenerNotFound:
 		return "kafka server: There is no listener on the leader broker that matches the listener on which metadata request was processed."
+	case ErrTopicDeletionDisabled:
+		return "kafka server: Topic deletion is disabled."
+	case ErrFencedLeaderEpoch:
+		return "kafka server: The leader epoch in the request is older than the epoch on the broker."
+	case ErrUnknownLeaderEpoch:
+		return "kafka server: The leader epoch in the request is newer than the epoch on the broker."
+	case ErrUnsupportedCompressionType:
+		return "kafka server: The requesting client does not support the compression type of given partition."
 	}
 
 	return fmt.Sprintf("Unknown error, how did this happen? Error code = %d", err)