Adding a bunch of gulp utilities

This should allow a developer to write a gulpfile in TypeScript to
compile a TypeScript project.

vinyl-source-stream/vinyl-source-stream-tests.ts

@@ -0,0 +1,8 @@
+/// <reference path="./vinyl-source-stream.d.ts"/>
+/// <reference path="../gulp/gulp.d.ts"/>
+import gulp = require("gulp");
+import vinylSourceStream = require("vinyl-source-stream");
+
+gulp.src("test.js")
+    .pipe(vinylSourceStream("foo.js"))
+    .pipe(gulp.dest("build"));

vinyl-source-stream/vinyl-source-stream.d.ts

@@ -0,0 +1,11 @@
+// Type definitions for vinyl-source-stream
+// Project: https://github.com/hughsk/vinyl-source-stream
+// Definitions by: Asana <https://asana.com>
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
+/// <reference path="../node/node.d.ts"/>
+
+declare module "vinyl-source-stream" {
+    function vinylSourceStream(filename: string): NodeJS.ReadWriteStream;
+    export = vinylSourceStream;
+}