-Rewrote JsonTextReader to use internal buffer to improve performance

-Improved JsonSerializer to cache contract/converters where possible to improve performance
-Improved JsonTextReader error message when additional JSON content found
-Fixed internal exception thrown when deserializing Decimal/DateTimeOffset/Byte lists
-Fixed various JsonTextReader bugs

Src/Newtonsoft.Json/Serialization/JsonArrayContract.cs

@@ -38,6 +38,7 @@ namespace Newtonsoft.Json.Serialization
   public class JsonArrayContract : JsonContract
   {
     internal Type CollectionItemType { get; private set; }
+    internal JsonContract CollectionItemContract { get; set; }
 
     private readonly bool _isCollectionItemTypeNullableType;
     private readonly Type _genericCollectionDefinitionType;