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

gulp-tsd/gulp-tsd-tests.ts

@@ -9,7 +9,7 @@ gulp.task("tsd", () => {
         .pipe(tsd());
 });
 
-gulp.task("tsd:options", callback => {
+gulp.task("tsd:options", (callback: any) => {
     tsd({
         command: "reinstall",
         config: "tsd.json"

gulp-tsd/gulp-tsd.d.ts

@@ -7,6 +7,7 @@
 /// <reference path="../gulp/gulp.d.ts" />
 
 declare module "gulp-tsd" {
+    import gulp = require('gulp');
 
     interface IOptions {
         command?: string;