updated version

- manually instaling yarn should no loonger beneeded
-  commented xvfb related stuff as test is diabled

.travis.yml

@@ -1,7 +1,7 @@
 sudo: false
 language: node_js
 node_js:
-  - "8.9.3"
+  - "10.16.1"
 env:
   - CXX=g++-5
 addons:
@@ -12,17 +12,15 @@ addons:
     - g++-5
     firefox: "latest"
 before_install:
-  - curl -o- -L https://yarnpkg.com/install.sh | bash -s -- --version 1.3.2
-  - export PATH=$HOME/.yarn/bin:$PATH
   - yarn global add node-gyp
 cache:
   yarn: true
 branches:
   except: 
     - gh-pages
 before_script:
-  - "export DISPLAY=:99.0"
-  - "sh -e /etc/init.d/xvfb start"
+#  - "export DISPLAY=:99.0"
+#  - "sh -e /etc/init.d/xvfb start"
   - sleep 3 # give xvfb some time to start
 script:
 #  - yarn test