.NET: Thin client: Do not buffer entire socket response

See ClientSocket.SendReceive: it buffers entire socket response into an array. Responses can be huge (with QueryCursor.GetAll and the like), so this can cause LOH allocations.

We should implement IBinaryStream over a socket instead.

This may cause situation when another socket call happens in the middle of data transfer (for example, GetBinaryTypeName while reading cursor data).