F# and C# addings (#189)

* F# - Binary Search

* C# - Double selection sort

* quick sort - f#

02_selection_sort/csharp/double_selection_sort/Program.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace SelectionSort
+{
+	class Program
+	{
+		static void Main(string[] args)
+		{
+			var numbers = new int[] { 4, 5, 1, 3, 10, 9, 6, 8, 7, 2 };
+			var sortedArr = SelectionSort(numbers);
+
+			Console.WriteLine(string.Join(',', sortedArr));
+		}
+
+		private static int[] SelectionSort(int[] array) 
+			=> SelectionSort(new LinkedList<int>(array)).ToArray();
+
+		private static IEnumerable<int> SelectionSort(LinkedList<int> list)
+		{
+			var minList = new LinkedList<int>();
+			var maxList = new LinkedList<int>();
+
+			while (list.Count != 0)
+			{
+				var min = list.Min();
+				list.Remove(min);
+				minList.AddLast(min);
+
+				var max = list.Max();
+				list.Remove(max);
+				maxList.AddFirst(max);
+			}
+
+			return minList.Union(maxList);
+		}
+	}
+}