Update Selenium Docker images from 2.46.0 to 2.48.2

.travis.yml

@@ -5,8 +5,8 @@ sudo: required
 services:
   - docker
 before_script:
-  - docker pull selenium/standalone-firefox:2.46.0
-  - docker pull selenium/standalone-chrome:2.46.0
+  - docker pull selenium/standalone-firefox:2.48.2
+  - docker pull selenium/standalone-chrome:2.48.2
 script:
   - npm test
   - dockers/Screenshotter/screenshotter.sh --verify

dockers/Screenshotter/screenshotter.sh

@@ -8,7 +8,7 @@
 # directly.
 
 status=0
-for browserTag in firefox:2.46.0 chrome:2.46.0; do
+for browserTag in firefox:2.48.2 chrome:2.48.2; do
     browser=${browserTag%:*}
     image=selenium/standalone-${browserTag}
     echo "Starting container for ${image}"