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
You don't need the same includes in both .h and .cpp.   Also please see my other comment regarding includes, c-style vs c++ include for c-libraries.