Pagination objects in PMA should have a 'type=pagination' field

Just like documents, menu, hst component, 'pagination' can better have a type field in its JSON PMA output. For example for documents this is one of

1. type = document
2. type = asset
3. type = imageset

for hst component it is

1. type = component
2. type = container
3. type = container-item

and for menu it is

1. type = menu

Pagination is flattened as a first class known PageModelEntity and can better also have a type field