Don't log to local filesystems

[imaginator]

Is there a reason to be writing logs to the local FS (and potentially fill the production FS)?

https://github.com/buddycloud/buddycloud-package/blob/master/projects/buddycloud-server-java/docker/log4j.properties#L10

[abmargb]

We are currently using the logstash forwarder, that requires the log file to be present in the file system.
We should use logstash log4j appenders instead so that create log files.