Generalizing python code generation for non-managed properties

[RubendeBruin]

None-managed properties can be changed by the user even if a node is managed. They need to be registered and stored when the scene is saved or copied. This is currently the job of the manager, which is undesirable.

[RubendeBruin]

Proposal:

• add a method "give_python_code_when_managed" method to Node.
• this node is to return the python code required to set the unmanaged properties to their non-default values
• this code is to be executed after all nodes have been created.

Example:

BallastTanks have "fill_pct", "free_flooding", and "density" as non-managed properties. the function could return

s['tank'].density = 1.025
s['tank'].fill_pct = 50

[RubendeBruin]

an other unmanaged property is "color".

This needs to be wrapped in try-except because nodes that are created by super-element may not exist anymore the next time the model is loaded (as the input files for those nodes may have changed)

So the python code is not practical.

Better to return the list of properties together with their values like so:

[
("density",1.025),
("fill_pct", 50)
]

should be a list because the order may be important.