Set up some sort of persistent logging

[jessepollak]

Right now, all of our logs disappear every time we create a new dokku instance — this is very very bad.

Things I would like:

• persistent logging across dokku deploys
• logging of all HTTP requests etc rather than just console.logs we add

@josephwegner mentioned he would look into this.

[josephwegner]

@jessepollak I'm having trouble SSHing into the dokku server, which will be a req. to setup logging. Next time we meet up on IRC, let's take a look at the SSH stuff and then I'll roll with this.