Option to generate types instead of interfaces

Hi!

Is it possible to add an option to generate

```
export type User = {
username?: string;
uuid?: string;
}
```

instead of

```
export interface User {
username?: string;
uuid?: string;
}
```

Sometimes it is necessary to prevent possible expansion of the type. Use case [here](https://www.typescriptlang.org/play?#code/CYUwxgNghgTiAEAzArgOzAFwJYHtVNQEFUBPAeQCMArcDABVigFsAKRHHALngCVwcYwADwBnDDCyoA5gBp4aANaocAd1QA+AJTcAbjizAA3AChjGEgAcEAVREgY8ALzwA3sfjy7MVMxAB+bjEJaRMPZGQDAPggySkTAF9TSQx7RCgwBABJW3tXd097HyZ-QPFY0PkI4CiYkONE4wgQDHgoUm42khNEIlJKGkwGGGYWTtaReByYTUN4AHo5+HMreABaeBwFYx7icmpaIZGxqAnsrxn5xeTU9IR1tKwIbd69gfpGVhd4ADpf49OpvB4hcFvBrjA0hk1mCmBZhpgsGAoBB4CoBApYDg0MBjEA)