Remove library tags, they aren't needed

lib/src/server/server.dart

 // Copyright (c) 2015, 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.
 
 /// Development server that compiles Dart to JS on the fly.
-library dev_compiler.src.server;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
 import 'package:analyzer/file_system/file_system.dart' show ResourceUriResolver;
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/src/generated/engine.dart'
     show AnalysisContext, ChangeSet;
 import 'package:analyzer/src/generated/error.dart';
@@ skipping 303 matching lines @@
   Source resolveAbsolute(Uri uri, [Uri actualUri]) {
     var src = resolver.resolveAbsolute(uri, actualUri);
     return src.exists() ? src : null;
   }
 
   Uri restoreAbsolute(Source source) => resolver.restoreAbsolute(source);
 }
 
 final _log = new Logger('dev_compiler.src.server');
 final _earlyErrorResult = new CheckerResults(const [], true);