improved interaction between exponentiateWholeNumber() and ComplexExponential.create()
improved interaction between exponentiateWholeNumber() and ComplexExponential.create()

It seemed necessary to handle the square root functionality ComplexExponential.create() needs in a dedicated function rather than through expoentiate() in order to avoid circularity, but as it stands, this solution seems messy.
AlexanderKindel/solver,AlexanderKindel/solver