Merge remote-tracking branch 'justadudewhohacks/master'

.travis.yml

@@ -7,6 +7,8 @@ node_js:
   - "8"
   # node 6 is not compatible with tfjs-node
   # - "6"
+services:
+  - xvfb
 env:
   global:
     - BACKEND_CPU=true EXCLUDE_UNCOMPRESSED=true
@@ -16,9 +18,6 @@ env:
 addons:
   chrome: stable
 install: npm install
-before_install:
- - export DISPLAY=:99.0
- - sh -e /etc/init.d/xvfb start
 script:
   - if [ $ENV == 'browser' ]; then npm run test-browser; fi
   - if [ $ENV == 'node' ]; then npm run test-node; fi