Add a quiet option to nuxeo launcher

Add a "-q" (quiet) option to nuxeo launcher for the start command :
Launcher command: java -Dlauncher.java.opts=-server -Xms512m -Xmx1024m -XX:MaxPermSize=512m -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000 -Dfile.encoding=UTF-8 -Djava.net.preferIPv4Stack=true -Djava.awt.headless=true -Dnuxeo.home=/opt/nuxeo-dm -Dnuxeo.conf=/etc/nuxeo-dm/nuxeo.conf -jar /opt/nuxeo-dm/bin/nuxeo-launcher.jar startbg
Nuxeo home: /opt/nuxeo-dm
Nuxeo configuration: /etc/nuxeo-dm/nuxeo.conf
Include template: /opt/nuxeo-dm/templates/common
Include template: /opt/nuxeo-dm/templates/default
Include template: /opt/nuxeo-dm/templates/postgresql
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