Uniformize logfiles content

Depending on the protocol you log into Zimbra (smtp, pop, imap, webmail, etc), the auth.log logfile is not populated with same lines.

The content (fields and fields order) is not the same, thus breaking any automatic grok matching.

Please rewrite the log functions so all protocols write the same fields, in the same order.
See: https://github.com/Zimbra/elastic-stack/issues/2

I suppose the issue is the same in other logs but this one, auth.log, is quite important.