Bad credentials should show the username

First of all this line should be INFO:

2012-12-13 19:23:05,281 [WARN ][http-8080-50    ][alks.jcommune.service.transactional.TransactionalUserService] - Bad credentials

Second, we need to show credentials that were tried there and the IP address of the guy (it might not work correctly with reverse proxy configured, but still in other cases we'll be in chocolate).