Make RaoParameters generic

[pet-mit]

Describe the current behavior

The RaoParameters object (same applies to its json representation) mixes business parameters (such as objective function) with serach-tree-specific parameters (such as maximum search depth).

Describe the expected behavior

Taking as an example PowSyBl's LoadFlowParameters, separate RaoParameters into:

• "business" RAO parameters that shall apply to any RAO implementation
• extensions containing implementation-specific parameters
  • begin with a SearchTeeRaoParameters extension,which contains parameters specific to SearchTree

Describe the motivation

This would help create a generic RAO API, and make the two following things possible:

• move the API to powsybl-core
• create new RAO implementations

Extra Information

No response

[pet-mit]

@pjeanmarie I think the best approach would be to draw a table of all RAO parameters here, and discuss together where each should go