Made AnimationEditor compatible with Dictionary SpriteMaps

Added MonoGame Pipeline's IntermediateSerializer and needed classes from the pipeline and  MonoGame.Framework.Utilities to make AnimationEditor capable of reading Dictionaries

AnimationEditor/MonoGame.Framework.Content.Pipeline/Serialization/Intermediate/Vector2Serializer.cs

@@ -0,0 +1,30 @@
+// MonoGame - Copyright (C) The MonoGame Team
+// This file is subject to the terms and conditions defined in
+// file 'LICENSE.txt', which is part of this source code package.
+
+using System.Collections.Generic;
+using System.Xml;
+
+namespace Microsoft.Xna.Framework.Content.Pipeline.Serialization.Intermediate
+{
+    [ContentTypeSerializer]
+    class Vector2Serializer : ElementSerializer<Vector2>
+    {
+        public Vector2Serializer() :
+            base("Vector2", 2)
+        {
+        }
+
+        protected internal override Vector2 Deserialize(string[] inputs, ref int index)
+        {
+            return new Vector2( XmlConvert.ToSingle(inputs[index++]),
+                                XmlConvert.ToSingle(inputs[index++]));
+        }
+
+        protected internal override void Serialize(Vector2 value, List<string> results)
+        {
+            results.Add(XmlConvert.ToString(value.X));
+            results.Add(XmlConvert.ToString(value.Y));
+        }
+    }
+}