Improve loading strategy
For now, the strategy is based on the loading keyword 'eager' or 'lazy'.
On list, it loads all eager fields and on form it loads all fields.
But if the screen has many views (especially form) which show different fields, the client will often load too many fields.
We could improve the behavior by tying the field to the views where it is displayed. So when selecting other fields to load we could limit the selection to other fields which share a view.
Also when a view load fields, it should try first the fields displayed the less (by chance it will be only display on the view) to reduce the number of field selected.