Support for DBML schemas

Feature Request
---

I'd like Mongoose to allow importing [dbml](https://www.dbml.org/home/) and turn it into multiple Mongoose schemas and models.

I.E.
```dbml
Table example {
id int [ unique ]
name text
}
```

Would turn into a mongoose schema:

```js
{
id: { type: Number, unique: true, required: true },
name: { type: String, required: true }
}
```

No files, tests, or entry points are named. Start by locating the existing schema and model creation APIs, then determine how DBML tables and fields should map to them; done means importing a DBML schema produces the expected Mongoose schemas and models, including the shown types, uniqueness, and required properties.

Written by the indexing model from the issue text.