Start modernization

Application/Feeds/Category.cs

@@ -1,15 +1,31 @@
 using System;
+using System.Collections.Generic;
+using Realms;
 
 namespace FeedCenter
 {
-    public partial class Category
+    public class Category : RealmObject
     {
+        private const string DefaultCategoryName = "< default >";
+
+        [PrimaryKey]
+        [MapTo("ID")]
+        public Guid Id { get; set; }
+        public string Name { get; set; }
+
+        [Ignored]
+        public ICollection<Feed> Feeds { get; set; }
+
         public static Category Create()
         {
-            return new Category { ID = Guid.NewGuid() };
+            return new Category { Id = Guid.NewGuid() };
+        }
+        public static Category CreateDefault()
+        {
+            return new Category { Id = Guid.NewGuid(), Name = DefaultCategoryName };
         }
 
-        public bool IsDefault => Name == "< default >";
+        public bool IsDefault => Name == DefaultCategoryName;
 
         // ReSharper disable once UnusedMember.Global
         public int SortKey => IsDefault ? 0 : 1;