Switch to Java 11 on travis
Switch to Java 11 on travis

Siedlerchr/jabref,Siedlerchr/jabref,JabRef/jabref,sauliusg/jabref,JabRef/jabref,zellerdev/jabref,zellerdev/jabref,JabRef/jabref,JabRef/jabref,sauliusg/jabref,sauliusg/jabref,Siedlerchr/jabref,sauliusg/jabref,zellerdev/jabref,zellerdev/jabref,zellerdev/jabref,Siedlerchr/jabref