Don't convert proto fields to camel case.

api/api.go

diff --git a/api/api.go b/api/api.go
index 434e4f4..6289bef 100644
--- a/api/api.go
+++ b/api/api.go
@@ -60,7 +60,7 @@
 	return &HTTPConnection{
 		client:      &http.Client{Timeout: time.Duration(1 * time.Second)},
 		credentials: "Basic " + base64.StdEncoding.EncodeToString([]byte(usernamePassword)),
-		marshaler:   &jsonpb.Marshaler{},
+		marshaler:   &jsonpb.Marshaler{OrigName: true},
 		// TODO(wsilberm): Use https
 		baseURL: "http://" + serverAddr,
 	}
@@ -111,7 +111,7 @@
 
 	httpResp, err := conn.client.Do(httpReq)
 	if err != nil {
-		return nil, fmt.Errorf("invalid response. CheckAvailability yielded error: %v", err)
+		return nil, fmt.Errorf("invalid response. %s yielded error: %v", rpcName, err)
 	}
 	return httpResp, nil
 }