[rsyslog] news and download link for 3.18.4

[Rainer Gerhards]

> somehow, i think that either something is messed up with the website
> cms or that the news/download has not been altered yet.
> 
> 	http://www.rsyslog.com/Downloads-index-req-viewdownload-cid-1-
> orderby-dateD.phtml
> -> no download link

This is the instable branch. I have to admit this is not well visible,
but there is a link to the stable releases on the top of that page, this
one:

http://www.rsyslog.com/Downloads-req-viewsdownload-sid-1.phtml

> http://www.rsyslog.com/index.php?name=News -> no news.

This, indeed, I have forgotten :) -- thx

Rainer