Persist log directory between deploys
Persist log directory between deploys

This is so we don't have logs in all different directories between
releases. In normal circumstances you want to see the logs
sequentially, even between deploys or rollbacks.

It also makes it easier for us to correctly rotate the logs, see #944.

openaustralia/morph,openaustralia/morph,openaustralia/morph,openaustralia/morph,openaustralia/morph,openaustralia/morph,openaustralia/morph