Moved application code to the Application layer

Imported Win10 project
Code cleanup
WIP - Use common UWP services for Win8.1 and Win10

ModernKeePass.Domain/Dtos/Credentials.cs

@@ -3,7 +3,7 @@
     public class Credentials
     {
         public string Password { get; set; }
-        public string KeyFilePath { get; set; }
+        public byte[] KeyFileContents { get; set; }
         // TODO: add Windows Hello
     }
 }