decide how to expose the wiring on the ProcNode API

[ichthyo]

Currently, each ProcNode contains a (protected) ref to a const WiringDescriptor. Only NodeFactory as a friend can access this information.

• determine which wiring information need to be accessible for cooperation partners, e.g. for conducting the render process
• find some way of making the ports iterable
• maybe we should completely expose the WiringDescriptor
• maybe even we drop the ProcNode as primary building block of the low-level model and use WiringDescriptor instead?

currently, this decision constitues a sort-of design deadlock in this area -- thus the high rating

[ichthyo]

not right now