Organize classes better

Closes #94

Octokit/Models/Response/User.cs

@@ -0,0 +1,32 @@
+using System;
+using System.Diagnostics;
+using System.Globalization;
+
+namespace Octokit
+{
+    /// <summary>
+    /// Represents a user on GitHub.
+    /// </summary>
+    [DebuggerDisplay("{DebuggerDisplay,nq}")]
+    public class User : Account
+    {
+        /// <summary>
+        /// Hex Gravatar identifier
+        /// </summary>
+        public string GravatarId { get; set; }
+
+        /// <summary>
+        /// Whether or not the user is an administrator of the site
+        /// </summary>
+        public bool SiteAdmin { get; set; }
+
+        internal string DebuggerDisplay
+        {
+            get
+            {
+                return String.Format(CultureInfo.InvariantCulture,
+                    "User: Id: {0} Login: {1}", Id, Login);
+            }
+        }
+    }
+}