Add date formatting and parsing code.

lib/i18n/date_symbols.dart

Index: lib/i18n/date_symbols.dart
===================================================================
--- lib/i18n/date_symbols.dart	(revision 0)
+++ lib/i18n/date_symbols.dart	(revision 0)
@@ -0,0 +1,53 @@
+// Copyright (c) 2012, 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("date_symbols");
+
+/**
+ * This holds onto information about how a particular locale formats dates. It
+ * contains mostly strings, e.g. what the names of months or weekdays are,
+ * but also indicates things like the first day of the week. We expect the data
+ * for instances of these to be generated out of ICU or a similar reference
+ * source. This is used in conjunction with the date_time_patterns, which
+ * defines for a particular locale the different named formats that will
+ * make use of this data.
+ */
+class DateSymbols {
+  final String NAME;
+  final List<String> ERAS, ERANAMES, NARROWMONTHS, STANDALONENARROWMONTHS,
+      MONTHS, STANDALONEMONTHS, SHORTMONTHS, STANDALONESHORTMONTHS, WEEKDAYS,
+      STANDALONEWEEKDAYS, SHORTWEEKDAYS, STANDALONESHORTWEEKDAYS,
+      NARROWWEEKDAYS, STANDALONENARROWWEEKDAYS, SHORTQUARTERS,
+      QUARTERS, AMPMS, DATEFORMATS, TIMEFORMATS;
+  final Map<String, String> AVAILABLEFORMATS;
+  final int FIRSTDAYOFWEEK;
+  final List<int> WEEKENDRANGE;
+  final int FIRSTWEEKCUTOFFDAY;
+
+  const DateSymbols([this.NAME,
+                     this.ERAS,
+                     this.ERANAMES,
+                     this.NARROWMONTHS,
+                     this.STANDALONENARROWMONTHS,
+                     this.MONTHS,
+                     this.STANDALONEMONTHS,
+                     this.SHORTMONTHS,
+                     this.STANDALONESHORTMONTHS,
+                     this.WEEKDAYS,
+                     this.STANDALONEWEEKDAYS,
+                     this.SHORTWEEKDAYS,
+                     this.STANDALONESHORTWEEKDAYS,
+                     this.NARROWWEEKDAYS,
+                     this.STANDALONENARROWWEEKDAYS,
+                     this.SHORTQUARTERS,
+                     this.QUARTERS,
+                     this.AMPMS,
+                     this.DATEFORMATS,
+                     this.TIMEFORMATS,
+                     this.AVAILABLEFORMATS,
+                     this.FIRSTDAYOFWEEK,
+                     this.WEEKENDRANGE,
+                     this.FIRSTWEEKCUTOFFDAY]);
+
+  toString() => NAME;
+}