Feature/install opentripplanner

This is an example of the service user creation task I've been using.

```yaml
- name: Create service account for pgweb
  user: name=pgweb
        system=yes
        home=/var/lib/pgweb
        shell=/bin/false
        state=present
```

Some notable bits:

- `system=yes`
- `/bin/false` or `/sbin/nologin` (this is a good thread on this in one of the `nyc-trees` PRs, but I haven't found it yet)
- Set `home` to something in `/var/lib`