Distribute `totalDraws` using ratio/probability vector `inputRatio` and randomly round each entry up or down such that the distribution results in an integer vector.
Returns an integer vector containing the number of units in `totalDraws` distributetd according to proportions in `inputRatio`.
NOTE: This is an internal function used for testing the C++-function distributeRandom which is used inside the C++-function recordSwap().
distributeRandom_cpp(inputRatio, totalDraws, seed)