Allows ACLs/settings in model config

/to @bajtos @ritch 

The PR allows acls and other setting properties to be specified in model-config.json.
> In fact, I had the code to group the model settings into a `settings` or `options` but thought it needs to be consistent with the model definitions.

Model definition allows you to place options either to the root object or to `options`, the latter taking precedence IIRC. In other words, the following is equivalent:

```
{ name: "Customer", base: "User" }
{ name: "Customer", options: { base: "User" }
```

The shorthand notation was introduced by #304 .

> One idea is to allow static properties to be described in LDL.

Let's leave that out of scope of this PR.