Fix .travis.yml

.travis.yml

@@ -1,34 +1,23 @@
 language: node_js
-sudo: false
+sudo: required
+os: linux
+dist: trusty
 node_js:
-- "6"
+  - "6"
 cache:
   directories:
   - node_modules
-matrix:
-  include:
-  - os: linux
-    sudo: required
-    dist: trusty
-    compiler: g++
-  - os: osx
-    osx_image: xcode7
-    compiler: clang
 addons:
   apt:
-    sources:
-    - ubuntu-toolchain-r-test
     packages:
-    - xutils-dev
-    - libxi-dev
-    - libxxf86vm-dev
-    - x11proto-xf86vidmode-dev
     - mesa-utils
     - xvfb
     - libgl1-mesa-dri
     - libglapi-mesa
     - libosmesa6
+before_script:
+  - export DISPLAY=:99.0; sh -e /etc/init.d/xvfb start
 script:
-- npm run ci
+  - npm run ci
 after_success:
   - './node_modules/.bin/nyc report --reporter=text-lcov | ./node_modules/.bin/coveralls'