add install4j install option for unix installer
add install4j install option for unix installer

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