DevOps

Adds salt states for setting up the app on a server, and a vagrant config for testing the prod environment locally.

/cc @jorgeer Please have a look and ask if you have any questions, if everything is OK I'll rebase and merge.

The database is not handled properly yet, we need to add `alembic` to handle migrations, now the app simply adds all missing tables on startup, which won't work when adding/changing/removing columns, but that can be another PR.
In addition to increased clarity, an external file would also be executable outside travis - win. I'll do that.