[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/xiang90/probing/server.go b/vendor/github.com/xiang90/probing/server.go
new file mode 100644
index 0000000..0e7b797
--- /dev/null
+++ b/vendor/github.com/xiang90/probing/server.go
@@ -0,0 +1,25 @@
+package probing
+
+import (
+	"encoding/json"
+	"net/http"
+	"time"
+)
+
+func NewHandler() http.Handler {
+	return &httpHealth{}
+}
+
+type httpHealth struct {
+}
+
+type Health struct {
+	OK  bool
+	Now time.Time
+}
+
+func (h *httpHealth) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	health := Health{OK: true, Now: time.Now()}
+	e := json.NewEncoder(w)
+	e.Encode(health)
+}