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/google.golang.org/grpc/go.mod b/vendor/google.golang.org/grpc/go.mod
index f296dcf..0418807 100644
--- a/vendor/google.golang.org/grpc/go.mod
+++ b/vendor/google.golang.org/grpc/go.mod
@@ -2,19 +2,19 @@
 
 require (
 	cloud.google.com/go v0.26.0 // indirect
+	github.com/BurntSushi/toml v0.3.1 // indirect
 	github.com/client9/misspell v0.3.4
 	github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b
 	github.com/golang/mock v1.1.1
 	github.com/golang/protobuf v1.2.0
-	github.com/kisielk/gotool v1.0.0 // indirect
 	golang.org/x/lint v0.0.0-20181026193005-c67002cb31c3
 	golang.org/x/net v0.0.0-20180826012351-8a410e7b638d
 	golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be
 	golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f // indirect
 	golang.org/x/sys v0.0.0-20180830151530-49385e6e1522
 	golang.org/x/text v0.3.0 // indirect
-	golang.org/x/tools v0.0.0-20180828015842-6cd1fcedba52
+	golang.org/x/tools v0.0.0-20190114222345-bf090417da8b
 	google.golang.org/appengine v1.1.0 // indirect
 	google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8
-	honnef.co/go/tools v0.0.0-20180728063816-88497007e858
+	honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099
 )