Fix chromedriver issues, and run headless on travis (#310)

* Fix chromedriver issues, and run headless on travis

* Explicitly set chrome window size

* Use travis chrome

* Try chrome beta

* Update chromedriver

* Remove virtual display from travis config

.travis.yml

@@ -1,24 +1,13 @@
-sudo: true
-dist: trusty
-
 language: python
 python:
   "3.6"
 cache: pip
 
 addons:
-  apt:
-    sources:
-      - google-chrome
-    packages:
-      - google-chrome-stable
-
-before_install:
-  - "export DISPLAY=:99.0"
-  - "/sbin/start-stop-daemon --start --quiet --pidfile /tmp/custom_xvfb_99.pid --make-pidfile --background --exec /usr/bin/Xvfb -- :99 -ac -screen 0 1280x1024x16"
+  chrome: beta
 
 install:
-  - wget http://chromedriver.storage.googleapis.com/2.29/chromedriver_linux64.zip
+  - wget http://chromedriver.storage.googleapis.com/2.32/chromedriver_linux64.zip
   - unzip chromedriver_linux64.zip
   - export PATH=$PATH:$(pwd)
   - chmod +x chromedriver