Fix utf8stream references

lib/http.js

@@ -9,7 +9,7 @@ function debug (x) {
 
 var sys = require('sys');
 var net = require('net');
-var Utf8Stream = require('utf8_stream').Utf8Stream;
+var Utf8Decoder = require('utf8decoder').Utf8Decoder;
 var events = require('events');
 var Buffer = require('buffer').Buffer;
 
@@ -202,7 +202,7 @@ IncomingMessage.prototype.setEncoding = function (enc) {
   // TODO check values, error out on bad, and deprecation message?
   this._encoding = enc.toLowerCase();
   if (this._encoding == 'utf-8' || this._encoding == 'utf8') {
-    this._decoder = new Utf8Stream();
+    this._decoder = new Utf8Decoder();
     this._decoder.onString = function(str) {
       this.emit('data', str);
     };