Update Intl pubspec for Dart 2.0 dev versions and fix METADATA

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=162249090
diff --git a/CHANGELOG.md b/CHANGELOG.md
index b4355e9..d3ef2d7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,6 @@
 ## 0.15.2
  * Group the padding digits to the left of the number, if present. e.g. 00,001.
+ * Update the SDK constraint for Dart 2.0 dev versions.
 
 ## 0.15.1
  * Use the platform.locale API to get the OS platform.
diff --git a/pubspec.yaml b/pubspec.yaml
index 1a70bd7..fd43467 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -4,7 +4,7 @@
 description: Contains code to deal with internationalized/localized messages, date and number formatting and parsing, bi-directional text, and other internationalization issues.
 homepage: https://github.com/dart-lang/intl
 environment:
-  sdk: '>=1.24.0 <2.0.0'
+  sdk: '>=1.24.0 <2.0.0-dev.infinity'
 documentation: http://www.dartdocs.org/documentation/intl/latest
 dependencies:
   path: '>=0.9.0 <2.0.0'