Refactoring of Boundaries implementations

[sebalaig]

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

• What is the current behavior? 2 problems:

1. Boundaries implemented for DanglingLines and HalfLines are very similar and some code can be factorized :

• getP()
• getQ()
• getAngle()
• getV() The only difference between both implementations is the way the terminal is retrieved.

2. HalfLine Boundary can be instanciated earlier in TieLine's constructor without calling attach

• If the current behavior is a bug, please provide the steps to reproduce and if possible a minimal demo of the problem No

• What is the expected behavior? DanglingLine::getP, getQ, getV and getA can be factorized. HalfLineBoundary::attach is removed

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

• Please tell us about your environment:

  • PowSyBl Version: ...
  • OS Version: ...

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

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