Move IGulpPlugin into gulp namespace, Gulp extends orchestrator, and gulp#watch method returns NodeJS.EventEmitter

run-sequence/run-sequence-tests.ts

@@ -5,7 +5,7 @@ import gulp = require("gulp");
 import tmp = require("run-sequence");
 var runSequence = tmp.use(gulp);
 
-gulp.task("run-sequence", callback => {
+gulp.task("run-sequence", (callback: any) => {
     runSequence("task1",
         ["task2", "task3"],
         "taks4",

run-sequence/run-sequence.d.ts

@@ -7,6 +7,7 @@
 /// <reference path="../gulp/gulp.d.ts" />
 
 declare module "run-sequence" {
+    import gulp = require('gulp');
 
     interface IRunSequence {
         (...streams: (string | string[] | gulp.ITaskCallback)[]): NodeJS.ReadWriteStream;