New attachment templates that support saving and opening attachment when composing message.

Wino.Core.UWP/Extensions/StorageFileExtensions.cs

@@ -0,0 +1,16 @@
+using System.Threading.Tasks;
+using Microsoft.Toolkit.Uwp.Helpers;
+using Wino.Core.Domain.Models.Common;
+
+namespace Wino.Core.UWP.Extensions
+{
+    public static class StorageFileExtensions
+    {
+        public static async Task<SharedFile> ToSharedFileAsync(this Windows.Storage.StorageFile storageFile)
+        {
+            var content = await storageFile.ReadBytesAsync();
+
+            return new SharedFile(storageFile.Path, content);
+        }
+    }
+}