Importer doesn't find team

Hi there -- I'm using slackarchive and the importer, and I'm noticing this chunk of code always fails from importer.go:

```
t := models.Team{}
if err := i.db.Teams.FindId(team.ID).One(&t); err == nil {
log.Debug("Team already exists: %s", t.ID)
} else {
// fails
return nil, err
}
```

What would create the team in the database? I can't find any team creation in the slackarchive or slackarchive-init projects.