Update Travis config

Author: kevinsawicki

Diff for: .travis.yml

@@ -1,6 +1,8 @@
 language: objective-c
-script: 'curl -s -H "Authorization: token $ATOM_ACCESS_TOKEN" -H "Accept: application/vnd.github.v3.raw"
-  https://api.github.com/repos/atom/apm/contents/script/build-package | sh'
-env:
-  global:
-    secure: jsi4e5aNS1RHLfC3JQRLOPDWKmND91scHilD05kBnG70uMh72c4AjDhZKU8uDPMZnQIbEkb0jvm2DQw6xWcmBko8Tx3eXVmTqTEiPAaQdfDbSKEk4fXeJjFrZqeAMUXFecRE5Z1gjU4m2NPTFwXoOqjApPhxVnlhSeKPMTFeC9s=
+
+notifications:
+  email:
+    on_success: never
+    on_failure: change
+
+script: 'curl -s https://raw.githubusercontent.com/atom/ci/master/build-package.sh | sh'

Diff for: README.md

@@ -1,4 +1,4 @@
-# Git Diff package
+# Git Diff package [![Build Status](https://travis-ci.org/atom/git-diff.svg?branch=master)](https://travis-ci.org/atom/git-diff)
 
 Marks lines in the editor gutter that have been added, edited, or deleted since
 the last commit.