Extend identity role model.

Marechai.Database/Models/ApplicationRole.cs

@@ -0,0 +1,25 @@
+using System;
+using Microsoft.AspNetCore.Identity;
+
+namespace Marechai.Database.Models
+{
+    public class ApplicationRole : IdentityRole
+    {
+        public ApplicationRole() => Created = DateTime.UtcNow;
+
+        public ApplicationRole(string name) : base(name)
+        {
+            Description = name;
+            Created     = DateTime.UtcNow;
+        }
+
+        public ApplicationRole(string name, string description) : base(name)
+        {
+            Description = description;
+            Created     = DateTime.UtcNow;
+        }
+
+        public string   Description { get; set; }
+        public DateTime Created     { get; set; }
+    }
+}