Modernize the package's style.

lib/src/stream_sink_transformer.dart

 // Copyright (c) 2016, 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.
 
-library async.stream_sink_transformer;
-
 import 'dart:async';
 
 import 'stream_sink_transformer/handler_transformer.dart';
 import 'stream_sink_transformer/stream_transformer_wrapper.dart';
 
 /// A [StreamSinkTransformer] transforms the events being passed to a sink.
 ///
 /// This works on the same principle as a [StreamTransformer]. Each transformer
 /// defines a [bind] method that takes in the original [StreamSink] and returns
 /// the transformed version. However, where a [StreamTransformer] transforms
@@ skipping 24 matching lines @@
       void handleDone(EventSink<T> sink)}) {
     return new HandlerTransformer<S, T>(handleData, handleError, handleDone);
   }
 
   /// Transforms the events passed to [sink].
   ///
   /// Creates a new sink. When events are passed to the returned sink, it will
   /// transform them and pass the transformed versions to [sink].
   StreamSink<S> bind(StreamSink<T> sink);
 }