Use IDE 1.8.1 for Travis CI

Author: sandeepmistry

.travis.yml

@@ -6,11 +6,8 @@ addons:
       - libstdc++6:i386
 env:
   global:
-    - IDE_VERSION=1.6.12
+    - IDE_VERSION=1.8.1
 before_install:
-  - /sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_1.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :1 -ac -screen 0 1280x1024x16
-  - sleep 3
-  - export DISPLAY=:1.0
   - wget http://downloads.arduino.cc/arduino-$IDE_VERSION-linux64.tar.xz
   - tar xf arduino-$IDE_VERSION-linux64.tar.xz
   - mv arduino-$IDE_VERSION $HOME/arduino-ide