README: Add Travis CI status badge. Update installation, contribution guidelines.
diff --git a/README.md b/README.md
index 63cecda..448b496 100644
--- a/README.md
+++ b/README.md
@@ -1,14 +1,17 @@
-fixnum
+Fixnum
 ======
 
 A fixed-width 32- and 64- bit integer library for Dart.
-- - -
+
+[![Build Status](https://travis-ci.org/dart-lang/fixnum.svg?branch=master)](https://travis-ci.org/dart-lang/fixnum)
+
+## Documentation
+
 The fixnum package provides data types for signed 32- and 64-bit integers.
 The integer implementations in this library are designed to work identically
 whether executed on the Dart VM or compiled to JavaScript.
 
-Installing
-----------
+## Installation
 
 Use [pub](http://pub.dartlang.org) to install this package. Add the following
 to your `pubspec.yaml` file: