Added function combineSamplingStatsEither.
Added functions resultItemToIntStatsEitherValue and resultItemToDoubleStatsValue.
Added function resultSourceToIntStatsEitherValues and resultSourceToDoubleStatsEitherValues.
Added new functions resultsToIntStatsEitherValues and resultsToDoubleStatsEitherValues.
Added new functions resultsToIntStatsEitherPairs and resultsToDoubleStatsEitherPairs.