Reduce session timeout for beer machine

Dear AMIV

I really like the beer in the beer machine so first of all, thank you really much. ❤

Now, being a board member and having more than one beer available I always had to stand by the beer machine until it finally discarded my card (to prevent the next person from using up my beloved beers). I always had a feeling that this timeout was really quite long. Now having taken a look at the code i found out that the session timeout is 8 seconds, which does seem rather long to me. So my suggestion is to halve the session timeout to 4 seconds (which I'd say is still sufficient to dispense another beer if needed).

Thank you very much for your consideration

Jonas - VIS Webmaster

P.S.: I am not sure whether the base.conf file in the config.example folder is actually the one used, but it was the only one I could find so that's what I changed