feat(typings): add typing specs

add test in gulpfile which will compile a basic TS file with generated
angular2.d.ts to ensure generated d.ts is valid syntactic TS

Adds support for enums in .d.ts generation pipeline.
Removes renaming reexports in http module.

modules/angular2/src/http/interfaces.ts

@@ -20,7 +20,7 @@ export interface IRequestOptions {
   cache?: RequestCacheOpts;
 }
 
-export interface Request {
+export interface IRequest {
   method: RequestMethods;
   mode: RequestModesOpts;
   credentials: RequestCredentialsOpts;
@@ -34,7 +34,7 @@ export interface ResponseOptions {
   url?: string;
 }
 
-export interface Response {
+export interface IResponse {
   headers: Headers;
   ok: boolean;
   status: number;
@@ -49,12 +49,14 @@ export interface Response {
   json(): Object;
 }
 
-export interface ConnectionBackend { createConnection(observer: any, config: Request): Connection; }
+export interface ConnectionBackend {
+  createConnection(observer: any, config: IRequest): Connection;
+}
 
 export interface Connection {
   readyState: ReadyStates;
-  request: Request;
-  response: Rx.Subject<Response>;
+  request: IRequest;
+  response: Rx.Subject<IResponse>;
   dispose(): void;
 }
 
@@ -81,4 +83,4 @@ export interface Connection {
  */
 // Prefixed as IHttp because used in conjunction with Http class, but interface is callable
 // constructor(@Inject(Http) http:IHttp)
-export interface IHttp { (url: string, options?: IRequestOptions): Rx.Observable<Response> }
+export interface IHttp { (url: string, options?: IRequestOptions): Rx.Observable<IResponse> }

modules/angular2/src/http/static_request.ts

@@ -1,6 +1,6 @@
 import {RequestMethods, RequestModesOpts, RequestCredentialsOpts} from './enums';
 import {URLSearchParams} from './url_search_params';
-import {IRequestOptions, Request as IRequest} from './interfaces';
+import {IRequestOptions, IRequest} from './interfaces';
 import {Headers} from './headers';
 import {BaseException, RegExpWrapper} from 'angular2/src/facade/lang';
 

modules/angular2/src/http/static_response.ts

@@ -1,4 +1,4 @@
-import {Response as IResponse, ResponseOptions} from './interfaces';
+import {IResponse, ResponseOptions} from './interfaces';
 import {ResponseTypes} from './enums';
 import {baseResponseOptions} from './base_response_options';
 import {BaseException, isJsObject, isString, global} from 'angular2/src/facade/lang';