Fixed the build

Author: sumagnadas

.travis.yml

@@ -45,6 +45,7 @@ addons:
       - libxcb-render0-dev
       - libxcb-image0-dev
       - libxcb-icccm4-dev
+      - libxcb-render-util0-dev
 install:
   - if [ "$TRAVIS_OS_NAME" = "windows" ]; then py -m pip install -r requirements.txt; fi
   - if [ "$TRAVIS_OS_NAME" = "linux" ]; then export DISPLAY=:99.0; /sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_99.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :99 -screen 0 1920x1200x24 -ac +extension GLX +render -noreset;sleep 3;pip3 install -r requirements.txt; fi