Export TransferProgressEvent from msRest.ts (#189)

lib/msRest.ts

@@ -1,7 +1,7 @@
 // Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License. See License.txt in the project root for license information.
 
-export { WebResource, HttpRequestBody, RequestPrepareOptions, HttpMethods, ParameterValue, RequestOptionsBase } from "./webResource";
+export { WebResource, HttpRequestBody, RequestPrepareOptions, HttpMethods, ParameterValue, RequestOptionsBase, TransferProgressEvent } from "./webResource";
 export { DefaultHttpClient } from "./defaultHttpClient";
 export { HttpClient } from "./httpClient";
 export { HttpHeaders } from "./httpHeaders";