Remove internal scrolling from most views

With the new `ScrollView`, most views don't need to define their own scrolling system.
This includes:
* [ ] `EditText`
* [ ] `TextArea`
* [x] `TextView`
* [x] `ListView`
* [x] `SelectView`

For `MenuPopup`, we'll need something more, as we want special treatment for delimiters: the frame should include things like `├ ┤` to match the delimiter. This requires the external view to track the current offset of the scrollview. So it'll still be internal scrolling, but maybe using a `ScrollView` instead of the current `ScrollBase`.