Minor modifications for http_header

This rearranges the logic a little so the majority of the code is not as far indented like it was originally.  I also added in the author of the xframe module which inspired this one.

I changed the connection error message to a timeout error message which more accurately describes the condition in which res is nil.  Finally, the description says that this module shows HTTP headers so I changed the line where headers are shown from a vprint to a normal print.

Let me know what you think, this is a lot of small changes.