.travis: use latest firefox, install chrome

.travis.yml

@@ -4,7 +4,12 @@
 
 sudo: false
 addons:
-  firefox: "42"
+  firefox: "latest"
+  apt:
+    sources:
+      - google-chrome
+    packages:
+      - google-chrome-stable
 language: python
 python:
   - "2.7"
@@ -29,8 +34,9 @@ matrix:
     - python: "3.4"
       env: DRIVER=tests/test_zopetestbrowser.py
 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
   # - sudo apt-get install libxss1 xdg-utils -y
   # - wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -
   # - sudo sh -c 'echo "deb http://dl.google.com/linux/chrome/deb/ stable main" >> /etc/apt/sources.list.d/google.list'