move logs to data directory in maintenance

[gsaudade99]

The pgcleanup script by default writes to /var/log/galaxy/. As I recall, we said this could be usefull information for future analysis so we should keep the logs.

Moving the logs from the root disk to nfs (data) disk should be okay for long time.

~$ du -sh /var/log/galaxy/
1.5G    /var/log/galaxy/

closes: https://github.com/usegalaxy-eu/issues/issues/968

[domgz]

This sounds good.

But I am just realizing, this puts the logs inside a VM disk right? (e.g. qcow file or similar). Is that intended? (then they can only be read from that VM)