Several issues are related to the behavior of complex fields (multi, composite and switchable) due to the complexity of the fields or of they transformers.

As a first step, we will introduce a new way to combine fields.

Assume that you have a field A (multi) that contains another field B (composite)
Until now (5.2.4) the field A (his transformer) had to handle the whole data structure, meaning, the Items/Properties used by himself, but also the Items/Properties used by B.
Due to this limitation we only support two levels of fields and with one combination A(multi) containing a B(composit).
It is currently not possible to have a:

• A (composit) containing B (multi)
• A (composit) containing B (composit)
• A (multi) containing a B (composit) containing a C (multi)
  ... and so on.

In order to solve this, we will introduce new transformers that are responsible to handle Items used by the next level of fields.

• A (multi) creates a list of Items. Eatch Items contains the values of B(Multi). A simply pass the Item to the field B, and B is then responsible to create the Properties/Item needed by himself.
  Doing this we will be able to easily have
• A (multi) containing B (composit) containing C (multi)....
  in fact any field structure.

The only limitation is that each entry of a multi field will be stored under a child Item of the field root item.

Tasks:

• create the new transformers
• review the complex fields (multi/composit/switchable) in order to support this new delegation logic (these fields have to stay compatible with the old transformers)
• add samples
• review documentation
• add UI tests