Improved nil handling for AidStationDetail model (computes expected efforts even if no split_times have been recorded for a split).
Improved nil handling for AidStationDetail model (computes expected efforts even if no split_times have been recorded for a split).

SplitTime/OpenSplitTime,voltagead/OpenSplitTime,SplitTime/OpenSplitTime,SplitTime/OpenSplitTime,voltagead/OpenSplitTime,voltagead/OpenSplitTime