CreateRunOptions when IniStates is given and IndPeriod_WarmUp is not = 0L

(transfer from remaining issue of ticket https://forge.irstea.fr/issues/5422) It says that when IniStates is given and IndPeriod_WarmUp is not = 0L in CreateRunOptions, the initial state is used at the beginning of the warmup period. Therefore we should improve the DOC. Check this happens really like this and proceed.