[Load flow] Make parameters natively copyable

[sylvlecl]

• Do you want to request a feature or report a bug?

Enhancement.

• What is the current behavior?

Copy of loadflow parameters is implemented through writing and reading to/from JSON. It works fine but does not seem very natural, and might not work in the unlikely case where an extension does not provide JSON serialization.

• What is the expected behavior?

Copy could be implemented through as straight POJO cloning. This would require that all load flow parameters extensions implement a clone or copy method.

• What is the motivation / use case for changing the behavior?

Making parameters copy independant from JSON serialization.

• Please tell us about your environment:

  • PowSyBl Version: 3.1.0

• Other information (e.g. detailed explanation, stacktraces, related issues, suggestions how to fix, links for us to have context, eg. stackoverflow, spectrum, etc)

Related issue : #1151