Check/Parameterize code in Economics

[malcolm-dsider]

+Check the algorithm for conventional stimulation cost ( = 1.05 * 1.15 * ccstimadjfactor * wellbores.ninj * 1.25), as it seems wrong, or at least too simplistic with built-in assumptions that should be parameterized

+Check the algorithm for conventional plant costs ( = 1.12 * 1.15 *ccplantadjfactor * 250E-6 * np.max(surfaceplant.HeatExtracted) * 1000.), as it seems wrong, or at least too simplistic with built-in assumptions that should be parameterized

@kfbeckers