Update .travis.yml

Author: Luc

.travis.yml

@@ -5,12 +5,7 @@ language: bash
 os:
   - linux
 
-before_install:
-  - "/sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_99.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :99 -ac -screen 0 1280x1024x16"
-
 before_script:
-  - "export DISPLAY=:99.0"
-  - sleep 3 # give xvfb some time to start
   - wget http://downloads.arduino.cc/arduino-1.8.5-linux64.tar.xz
   - tar xf arduino-1.8.5-linux64.tar.xz
   - mv arduino-1.8.5 $HOME/arduino_ide