Update selenium server to 3.7.1

.travis.yml

@@ -43,12 +43,12 @@ before_install:
   - sh -e /etc/init.d/xvfb start
   - export DISPLAY=:99.0
   # Get Selenium
-  - wget http://selenium-release.storage.googleapis.com/3.6/selenium-server-standalone-3.6.0.jar
+  - wget http://selenium-release.storage.googleapis.com/3.7/selenium-server-standalone-3.7.1.jar
   # Check java
   - java -version
   - sudo apt-get install oracle-java8-installer
   - java -version
-  - java -jar selenium-server-standalone-3.6.0.jar -log selenium.log > /dev/null &
+  - java -jar selenium-server-standalone-3.7.1.jar -log selenium.log > /dev/null &
   - nohup bash -c "webdriver-manager start 2>&1 &"
   - sleep 10