Add GPL modules

MediaBrowser.Model/Extensions/ListHelper.cs

@@ -0,0 +1,24 @@
+using System;
+
+namespace MediaBrowser.Model.Extensions
+{
+    public static class ListHelper
+    {
+        public static bool ContainsIgnoreCase(string[] list, string value)
+        {
+            if (value == null)
+            {
+                throw new ArgumentNullException("value");
+            }
+
+            foreach (var item in list)
+            {
+                if (string.Equals(item, value, StringComparison.OrdinalIgnoreCase))
+                {
+                    return true;
+                }
+            }
+            return false;
+        }
+    }
+}