Added taglib "http://java.sun.com/jsp/jstl/core" to welcome.jsp.
Required adding Maven dependencies "javax.servlet:jstl:1.2" and
"taglibs:standard:1.1.2" to pom.xml; otherwise Eclipse would report
error "Can not find the tag library descriptor for
"http://java.sun.com/jsp/jstl/core"" in welcome.jsp.