Optional dangling line generation part

[annetill]

Describe the current behavior

A dangling line can have a generation part. It seems that these information are not exposed in pypowsybl.

Describe the expected behavior

Should be exposed.

Describe the motivation

No response

Extra Information

No response

[HugoKulesza]

@geofjamg should we add these new informations as optional columns in the current dangling lines dataframe or in a new distinct dataframe ?

[geofjamg]

As this is a one to one relation between dangling line and generation object I would merge it as optional columns in dangling line dataframe.