update selenium=3.4.3 in travis (#841)
update selenium=3.4.3 in travis (#841)


emanlove/robotframework-selenium2library,emanlove/robotframework-selenium2library,rtomac/robotframework-selenium2library,robotframework/SeleniumLibrary,SergiuTudos/Selenium2Library,emanlove/robotframework-selenium2library,SergiuTudos/Selenium2Library,SergiuTudos/Selenium2Library,rtomac/robotframework-selenium2library,robotframework/SeleniumLibrary,robotframework/SeleniumLibrary,rtomac/robotframework-selenium2library