public static String unEscape(String s) {
        Matcher m = backSlash.matcher(s);
        if (! m.find()) {
            return s;
        }
        m = backSlashN.matcher(s);
        if (m.find()) {
            s = m.replaceAll("\n");
        }
        m = backSlashT.matcher(s);
        if (m.find()) {
            s = m.replaceAll("\t");
        }
        m = backSlash2.matcher(s);
        if (m.find()) {
            s = m.replaceAll("\\\\");
        }
        return s;
    }
Un-escapes previously escaped string.
note: look at com.yahoo.config.StringNode.unescapeQuotedString()

@param s String that might need un-escaping
@return Returns un-escaped string
vespalog/src/main/java/com/yahoo/log/VespaFormatter.java