Roll Observatory packages and add a roll script

intl/lib/number_symbols.dart

-// 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 number_symbols;
-
-/**
- * This holds onto information about how a particular locale formats numbers. It
- * contains strings for things like the decimal separator, digit to use for "0"
- * and infinity. We expect the data for instances to be generated out of ICU
- * or a similar reference source.
- */
-class NumberSymbols {
-  final String NAME;
-  final String DECIMAL_SEP,
-      GROUP_SEP,
-      PERCENT,
-      ZERO_DIGIT,
-      PLUS_SIGN,
-      MINUS_SIGN,
-      EXP_SYMBOL,
-      PERMILL,
-      INFINITY,
-      NAN,
-      DECIMAL_PATTERN,
-      SCIENTIFIC_PATTERN,
-      PERCENT_PATTERN,
-      CURRENCY_PATTERN,
-      DEF_CURRENCY_CODE;
-
-  const NumberSymbols({this.NAME, this.DECIMAL_SEP, this.GROUP_SEP,
-      this.PERCENT, this.ZERO_DIGIT, this.PLUS_SIGN, this.MINUS_SIGN,
-      this.EXP_SYMBOL, this.PERMILL, this.INFINITY, this.NAN,
-      this.DECIMAL_PATTERN, this.SCIENTIFIC_PATTERN, this.PERCENT_PATTERN,
-      this.CURRENCY_PATTERN, this.DEF_CURRENCY_CODE});
-
-  toString() => NAME;
-}