add ps:restore to start applications which weren't manually stopped

[kdomanski]

Allows e.g. restarting previously running apps on reboot.

depends on #1610

[michaelshobbs]

Hmm, this is interesting. We could potentially use this in /etc/init/dokku-redeploy.conf instead of ps:restartall. @josegonzalez thoughts?

[josegonzalez]

@kdomanski we merged your post-stop plugin trigger, so can you remove that from this pr?

@michaelshobbs how would that work?

[michaelshobbs]

@josegonzalez sed -i 's/ps:restartall/ps:restore' /etc/init/dokku-redeploy.conf
because ps:restore is a filtered list of apps to restart instead of all apps i think this might make more sense to use to start apps on boot. maybe i'm missing something though.

EDIT: @kdomanski how do you use this functionality?

[kdomanski]

@michaelshobbs
dokku ps:restore as a oneshot supervisord task inside a container.
Before we used a systemd unit like this.

[josegonzalez]

@michaelshobbs that might work. Any objections against this PR as is? We can test the reboot functionality separately from this.

[josegonzalez]

@michaelshobbs Can we merge as is and have a separate pr that redoes our restart strategy?

[michaelshobbs]

yes