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/python/protos/schema.proto b/python/protos/schema.proto
new file mode 100644
index 0000000..2edd85a
--- /dev/null
+++ b/python/protos/schema.proto
@@ -0,0 +1,40 @@
+syntax = "proto3";
+
+option go_package = "github.com/opencord/voltha-protos/go/schema";
+
+package schema;
+
+import "google/api/annotations.proto";
+import "google/protobuf/empty.proto";
+
+// Contains the name and content of a *.proto file
+message ProtoFile {
+    string file_name = 1;  // name of proto file
+    string proto = 2;  // content of proto file
+    bytes descriptor = 3;  // compiled descriptor for proto (zlib compressed)
+}
+
+// Proto files and compiled descriptors for this interface
+message Schemas {
+
+    // Proto files
+    repeated ProtoFile protos = 1;
+
+    // Proto file name from which swagger.json shall be generated
+    string swagger_from = 2;
+
+    // Proto file name from which yang schemas shall be generated
+    string yang_from = 3;
+}
+
+// Schema services
+service SchemaService {
+
+    // Return active grpc schemas
+    rpc GetSchema(google.protobuf.Empty) returns (Schemas) {
+        option (google.api.http) = {
+            get: "/schema"
+        };
+    }
+
+}