Run mariadb and the minecraft game server with eatmydata

A lot of our slowdown currently is due to IO load. We can probably reduce some of this by disabling all fsync calls on write, using the eatmydata wrapper.

This issue requests:

• Launch the minecraft game server with eatmydata - should be a simple tweak to the launch script
• Launch mariadb with eatmydata - a symlink or change to launch script could work
• Ditto overviewer
• Observe IO load before and after the change, using iotop, htop's IO view, etc

https://manpages.debian.org/testing/eatmydata/eatmydata.1.en.html