Port !stats, !role, !wiki and !slap, fix messages in rank, add roleselfservicemodel to db

Geekbot.net/Database/Models/RoleSelfServiceModel.cs

@@ -1,7 +1,17 @@
-namespace Geekbot.net.Database.Models
+using System.ComponentModel.DataAnnotations;
+
+namespace Geekbot.net.Database.Models
 {
     public class RoleSelfServiceModel
     {
+        [Key]
+        public int Id { get; set; }
         
+        [Required]
+        public long GuildId { get; set; }
+        
+        public long RoleId { get; set; }
+        
+        public string WhiteListName { get; set; }
     }
 }