Allow BPMN2 subprocess object 'expand' and 'collapse' from Portal view of model

In BPMN2 notation the 'expand' and 'collapse' functionality of subprocess objects is only available when editing the repository version of the model.

It would be extremely useful to be able to access that functionality from the published Portal view of the model so that readers can choose whether to show suprocess in context with its parent model without having to toggle between the levels.

Expanded models should be active and visible through as many different levels as required from the parent model.

All visible expanded views should be active for Highlighting

The action should have no intrinsic impact on the layout of the model(s) and should be a per user basis. This means that different people should be able to set their own view detail and save as bookmark