Anything that is not `-` or `date` should be use as type for interfaces

As stated.

Something like:

```
type Custom struct {
    MyValue `ts:"MyCustomType"`
}
```

Should become:

```
interface Custom {
    my_value: MyCustomType
}
```

For importing the types, I use a script with something like `echo "import {Type} from '@types'" > src/types/golang.ts` before running struct2ts, if someone is wondering.