mediawiki: one action per line in rsyslog config

rsyslog requires that each action (that is, each log destination) be specified
on a separate line. The fact that the current configuration doesn't do that is
the reason why the apache2 log on fluorine is empty.

Change-Id: I7d25f036872c76aaac086d8967a3d2ce716d3dd5
Merge "mediawiki: one action per line in rsyslog config" into production