Add database entities for USB vendor and product IDs.

DiscImageChef.Database/Models/UsbVendor.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+
+namespace DiscImageChef.Database.Models
+{
+    public class UsbVendor
+    {
+        public UsbVendor() { }
+
+        public UsbVendor(ushort id, string vendor)
+        {
+            Id        = id;
+            Vendor    = vendor;
+            AddedWhen = ModifiedWhen = DateTime.UtcNow;
+        }
+
+        [Key]
+        public ushort Id { get;             set; }
+        public string   Vendor       { get; set; }
+        public DateTime AddedWhen    { get; set; }
+        public DateTime ModifiedWhen { get; set; }
+
+        public virtual ICollection<UsbProduct> Products { get; set; }
+    }
+}