Cut a release for the fix in 5baa1c5.

See #46
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 15112fd..d8e4cf8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.13.3+4
+
+* Use the proper `usage` getter in the README.
+
 ## 0.13.3+3
 
 * Add an explicit default value for the `allowTrailingOptions` parameter to `new
diff --git a/pubspec.yaml b/pubspec.yaml
index 326ef0e..34688a2 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: args
-version: 0.13.3+3
+version: 0.13.3+4
 author: "Dart Team <misc@dartlang.org>"
 homepage: https://github.com/dart-lang/args
 description: >