Fix typo in example (\b should be \n in string literal).

This closes SF bug #414279.

Doc/lib/libasyncore.tex

@@ -178,7 +178,7 @@ class http_client(asyncore.dispatcher):
         self.path = path
         self.create_socket(socket.AF_INET, socket.SOCK_STREAM)
         self.connect( (host, 80) )
-        self.buffer = 'GET %s HTTP/1.0\r\b\r\n' % self.path
+        self.buffer = 'GET %s HTTP/1.0\r\n\r\n' % self.path
         
     def handle_connect(self):
         pass