message: docs(array-types): add section for why "type" is always required
diff: @@ -25,3 +25,7 @@ class ModelClass {
  Mainly, because mongoose documents and their arrays fields have their pre-build methods, which slightly differ from `Array.method.prototype`. But at runtime, these methods already exist (because an array is always an mongoose array). So, using `type[]` is just more convenient way to write a shorter type instead of the `mongoose.Types` if the functions are not used.
  For more information you could look at [GitHub issue #509](https://github.com/typegoose/typegoose/issues/509).
  +
  +## Why is the `type` option always required?
  +
  +Because [Reflection](https://www.typescriptlang.org/docs/handbook/decorators.html#metadata) currently does not give out detailed information, it only "dumbs down" the type to `Array`, see [typescript issue #300](https://github.com/typegoose/typegoose/issues/300) for more.
  