Added the XmlFormatWriter/Reader
diff --git a/src/ProtocolBuffers/ICodedOutputStream.cs b/src/ProtocolBuffers/ICodedOutputStream.cs
index 56ee5b6..94aeff0 100644
--- a/src/ProtocolBuffers/ICodedOutputStream.cs
+++ b/src/ProtocolBuffers/ICodedOutputStream.cs
@@ -12,7 +12,11 @@
         void Flush();

 

         [Obsolete]

-        void WriteUnknownGroup(int fieldNumber, string fieldName, IMessageLite value);

+        void WriteUnknownGroup(int fieldNumber, IMessageLite value);

+        void WriteUnknownBytes(int fieldNumber, ByteString value);

+        [CLSCompliant(false)]

+        void WriteUnknownField(int fieldNumber, WireFormat.WireType wireType, ulong value);

+

         void WriteMessageSetExtension(int fieldNumber, string fieldName, IMessageLite value);

         void WriteMessageSetExtension(int fieldNumber, string fieldName, ByteString value);