src/main/java/com/papertrailapp/logback/Syslog4jAppender.java
public int getSeverityForEvent(Object eventObject) {
        if (eventObject instanceof ILoggingEvent) {
            ILoggingEvent event = (ILoggingEvent) eventObject;
            return LevelToSyslogSeverity.convert(event);
        } else {
            return SyslogIF.LEVEL_INFO;
        }
    }
public int getSeverityForEvent(Object eventObject) {
        if (eventObject instanceof ILoggingEvent) {
            ILoggingEvent event = (ILoggingEvent) eventObject;
            return LevelToSyslogSeverity.convert(event);
        } else {
            return SyslogIF.LEVEL_INFO;
        }
    }
Convert a level to equivalent syslog severity. Only levels for printing
methods i.e DEBUG, WARN, INFO and ERROR are converted.

@see ch.qos.logback.core.net.SyslogAppenderBase#getSeverityForEvent(java.lang.Object)