query.go
func ParallelSelect(original Enumerable, operation Transform) Enumerable {
	return parallelSelecter{
		original:  original,
		operation: operation,
	}
}
func ParallelSelect(original Enumerable, operation Transform) Enumerable {
	return parallelSelecter{
		original:  original,
		operation: operation,
	}
}
// ParallelSelect creates an Enumerable which will use all logically available CPUs to
// execute a Transform.