Lotus::Model::Configuration#adapter now takes in hash params

Before:

```
adapter :sqlite3, :sql, URI, default: false
```

After:

```
adapter name: :sqlite3, type: :sql, uri: URI, default: false
```
I think it's safe to drop this check here for two reasons:
  1. It's private API
  2. We already check developer input from `Configuration#adapter`, which is public API and happens before of this.