Bump the version to 2.0.3. (#15)

CHANGELOG.md

diff --git a/CHANGELOG.md b/CHANGELOG.md
index cb13d7b..9375a9c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 2.0.3
+
+* Fix new strong-mode warnings.
+
 ## 2.0.2
 
 * Fix all strong-mode warnings.

pubspec.yaml

diff --git a/pubspec.yaml b/pubspec.yaml
index 01cb528..c2b9f55 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: json_rpc_2
-version: 2.0.2
+version: 2.0.3
 author: Dart Team <misc@dartlang.org>
 description: An implementation of the JSON-RPC 2.0 spec.
 homepage: http://github.com/dart-lang/json_rpc_2