[VOL-2235] Mocks and interfaces for rw-core

This update consists of mocks that are used by the rw-core
during unit testing.  It also includes interfaces used for unit
tests.

Change-Id: I20ca1455c358113c3aa897acc6355e0ddbc614b7
diff --git a/vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/doc.go b/vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/doc.go
new file mode 100644
index 0000000..b6e5ddf
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/grpc-gateway/runtime/doc.go
@@ -0,0 +1,5 @@
+/*
+Package runtime contains runtime helper functions used by
+servers which protoc-gen-grpc-gateway generates.
+*/
+package runtime