file io

- We still need to come up with a naming metaphor for this!
- it is a pipeline communication to stream a file from a server to a client.
- It follows a model similar to: http://zguide.zeromq.org/c:fileio3
This is c-type of defining a struct. You do not need the typedef at all. A struct is the same thing as a class but all its members are by default public. Nothing more and  nothing less. 

 you only need this. 
```
struct DataChunk {
uint8_t* data = nullptr;
size_t size = 0;

   void Reset(){
      if(data != nullptr){
         free(data);
      }
      data = nullptr;
      size = 0;
   }
   ~DataChunk(){
      Reset();
   }
}
```