Move tools to tool folder.

pkg/front_end/tool/_fasta/run.dart

Index: pkg/front_end/tool/_fasta/run.dart
diff --git a/pkg/front_end/tool/_fasta/run.dart b/pkg/front_end/tool/_fasta/run.dart
deleted file mode 100644
index f42a5ef202ce9982e8c9e2eabb0d1b62223f6fe6..0000000000000000000000000000000000000000
--- a/pkg/front_end/tool/_fasta/run.dart
+++ /dev/null
@@ -1,7 +0,0 @@
-// Copyright (c) 2017, 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.
-
-import 'package:front_end/src/fasta/run.dart' show mainEntryPoint;
-
-main(List<String> arguments) => mainEntryPoint(arguments);