Showcase the use of sorted view

sorted_view_example.cpp

// 1. Create the sorted view
auto sv = make_sorted_view(first_name, last_name, country, sport, 
		years, gender, medals_gold, medals_silver, medals_bronze, medals_total);

sv.sort<0>(std::less<>{}); // 2. Sort by first name	

for (size_t i = 0; i < sv.size<0>(); i++) printf("{ %s-%s-%s }\n",
	sv.at<0>(i).c_str(), // 3. access the ith sorted element of sequence 0
	sv.at<1>(i).c_str(), 
	sv.at<2>(i).c_str());