Send headers from server to client with httpbeast

[demetera]

Thanks a lot. Based on this example I will learn how to proceed further. In the 
meantime there's a question, why instead of just passing header to the function 
as a string, need to create additional type and another procedure to create 
headers. I guess, it's C/C++ legacy to save memory / less binary size, 
flexibility etc. and I didn't get to it yet.