fix spelling in core libraries

sdk/lib/io/http.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
 /**
  * HTTP status codes.
  */
 abstract class HttpStatus {
@@ skipping 1156 matching lines @@
    * Respond with a redirect to [location].
    *
    * The URI in [location] should be absolute, but there are no checks
    * to enforce that.
    *
    * By default the HTTP status code `HttpStatus.MOVED_TEMPORARILY`
    * (`302`) is used for the redirect, but an alternative one can be
    * specified using the [status] argument.
    *
    * This method will also call `close`, and the returned future is
-   * the furure returned by `close`.
+   * the future returned by `close`.
    */
   Future redirect(Uri location, {int status: HttpStatus.MOVED_TEMPORARILY});
 
   /**
    * Detaches the underlying socket from the HTTP server. When the
    * socket is detached the HTTP server will no longer perform any
    * operations on it.
    *
    * This is normally used when a HTTP upgrade request is received
    * and the communication should continue with a different protocol.
@@ skipping 534 matching lines @@
   /**
    * Set this property to [:true:] if this request should
    * automatically follow redirects. The default is [:true:].
    *
    * Automatic redirect will only happen for "GET" and "HEAD" requests
    * and only for the status codes [:HttpHeaders.MOVED_PERMANENTLY:]
    * (301), [:HttpStatus.FOUND:] (302),
    * [:HttpStatus.MOVED_TEMPORARILY:] (302, alias for
    * [:HttpStatus.FOUND:]), [:HttpStatus.SEE_OTHER:] (303) and
    * [:HttpStatus.TEMPORARY_REDIRECT:] (307). For
-   * [:HttpStatus.SEE_OTHER:] (303) autmatic redirect will also happen
+   * [:HttpStatus.SEE_OTHER:] (303) automatic redirect will also happen
    * for "POST" requests with the method changed to "GET" when
    * following the redirect.
    *
    * All headers added to the request will be added to the redirection
    * request(s). However, any body send with the request will not be
    * part of the redirection request(s).
    */
   bool followRedirects;
 
   /**
@@ skipping 281 matching lines @@
 class RedirectException implements HttpException {
   final String message;
   final List<RedirectInfo> redirects;
 
   const RedirectException(this.message, this.redirects);
 
   String toString() => "RedirectException: $message";
 
   Uri get uri => redirects.last.location;
 }