[skip ci] Update travis config

Author: tedium-bot

.travis.yml

@@ -1,28 +1,22 @@
 language: node_js
 sudo: false
-matrix:
-  include:
-  - node_js: stable
-    script: xvfb-run wct
-    addons:
-      firefox: latest
-      apt:
-        sources:
-        - google-chrome
-        packages:
-        - google-chrome-stable
-  - node_js: node
-    script:
-    - |
-      if [ "${TRAVIS_PULL_REQUEST}" = "false" ]; then
-        wct -s 'default'
-      fi
 before_script:
-- npm install web-component-tester
-- npm install bower
-- export PATH=$PWD/node_modules/.bin:$PATH
-- bower install
+  - npm install web-component-tester
+  - npm install bower
+  - 'export PATH=$PWD/node_modules/.bin:$PATH'
+  - bower install
 env:
   global:
-  - secure: TcDqx+YdNCa/DRQjdKt9dgYCPgXtPl2EZ7Nnv6bRvbcmUjW2eSr7Zwb+e0fO8wgwms/RqFaVx+u5jo7D1lnC4Ybcg1HKiMOvCyzY36MjF9oB/VKSEUC+p4tMVQfw1IZ/RmK3dD+WEWaoT/EKmNfctz7v5kR+yk2lZo44D9I7rrc=
-  - secure: nh65tvhnhOrK05qKvDJKMV7Jm9yiCoG1wFkP3ZnqOHix9Ny+KmcTa41Bl6NXQdvYaMTFtzS7lMZX5cqIziyKyGWHVN30LzGMHJNz12fhcMi3nJ84trhQGcu/9qR9yDv16q9ouGlcz1VxnDOHaRAHnIKjLIbhN3aJtMtZBbnWihA=
+    - secure: TcDqx+YdNCa/DRQjdKt9dgYCPgXtPl2EZ7Nnv6bRvbcmUjW2eSr7Zwb+e0fO8wgwms/RqFaVx+u5jo7D1lnC4Ybcg1HKiMOvCyzY36MjF9oB/VKSEUC+p4tMVQfw1IZ/RmK3dD+WEWaoT/EKmNfctz7v5kR+yk2lZo44D9I7rrc=
+    - secure: nh65tvhnhOrK05qKvDJKMV7Jm9yiCoG1wFkP3ZnqOHix9Ny+KmcTa41Bl6NXQdvYaMTFtzS7lMZX5cqIziyKyGWHVN30LzGMHJNz12fhcMi3nJ84trhQGcu/9qR9yDv16q9ouGlcz1VxnDOHaRAHnIKjLIbhN3aJtMtZBbnWihA=
+node_js: 4
+addons:
+  firefox: '42.0'
+  apt:
+    sources:
+      - google-chrome
+    packages:
+      - google-chrome-stable
+script:
+  - xvfb-run wct
+  - "if [ \"${TRAVIS_PULL_REQUEST}\" = \"false\" ]; then wct -s 'default'; fi"