misc: update dev_dependencies to support latest SDK (flutter#4)

Author: kevmoo

pubspec.yaml

@@ -1,5 +1,5 @@
 name: term_glyph
-version: 1.0.0
+version: 1.0.1-dev
 description: Useful glyphs and Windows-safe equivalents.
 author: Dart Team <[email protected]>
 homepage: https://github.com/dart-lang/term_glyph
@@ -9,5 +9,5 @@ environment:
 
 dev_dependencies:
   csv: '^3.0.0'
-  dart_style: '^0.2.0'
-  test: '^0.12.0'
+  dart_style: '>=0.2.0 <2.0.0'
+  test: '>=0.12.0 <2.0.0'

tool/generate.dart

@@ -8,12 +8,12 @@ import 'package:csv/csv.dart';
 
 void main() {
   var csv = new CsvCodec(eol: "\n");
-  var data = csv.decode(new File("data.csv").readAsStringSync());
+  var data = csv.decoder.convert(new File("data.csv").readAsStringSync());
 
   // Remove comments and empty lines.
   data.removeWhere((row) => row.length < 3);
 
-  var file = new File("lib/src/generated.dart").openSync(mode: FileMode.WRITE);
+  var file = new File("lib/src/generated.dart").openSync(mode: FileMode.write);
   file.writeStringSync("""
     // 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