add Programmyday form github

UmlautsExtentions/Program.cs

@@ -0,0 +1,20 @@
+using System.Security.Cryptography.X509Certificates;
+
+namespace UmlautsExtentions
+{
+    internal class Program
+    {
+        static void Main(string[] args)
+        {
+            string input = "Ueber ein leben hinaus, aeßert man sich nicht.";
+            Console.WriteLine(input.Umlauts());
+        }
+    }
+    static class UmlautsExtentions
+    {
+        public static string Umlauts(this string input)
+        {
+            return input.Replace("ae","ä").Replace("oe","ö").Replace("ue","ü").Replace("Ae", "Ä").Replace("Oe", "Ö").Replace("Ue", "Ü");
+        }
+    }
+}