Allows ACLs/settings in model config

/to @bajtos @ritch 

The PR allows acls and other setting properties to be specified in model-config.json.
> Are you proposing to support both options and top-level properties to be consistent with model definitions?

Rather not. The intention of top-level properties was to decrease nesting level for well-known options like "base", "relations", "acl".

For everything else, it's better to keep it nested in `options` by convention.

As I wrote in my earlier comment, the top level should ideally have only a small set of well-defined items:

```js
{
  dataSource: "db",
  relations: { /* ... */ },
  acls: [ /* ... */ ],
  options: { /* ... */ }
}
```