Size borefield configuration function

[tblanke]

Hi @wouterpeere ,

As already dicussed It would be nice to reimplement a borefield sizing method.

With best regards
@tblanke

[wouterpeere]

If issue #322 is implemented, this issue can be solved.
The idea is to create a function with the following inputs (shape, max length x, max length y, min Bx, max Bx, min By, max Bx, min H, max H) which contains an objective function that sizes the borefield for a particular configuration and returns the total borehole length.

This function can than be used as an input to the optuna hyberparameter optimisation function to find the minimum value. The maximum number of iterations can be set here.