[PATCH] HttpHdrSc c++ refactoring

Hi all,
  as a followup to the HttpHdrCc work, the attached patch (with 20
lines of context) c++-refactors the HttpHdrSc class.
It doesn't attempt to optimize parsing - not worth the hassle, even
though the current parser does type trickery which I would really like
to get rid of, but for surrogate-cotrol I don't believe it's worth the
hassle.
It does get rid of a string-copy by implementing a strnrchr() function
- one less TODO in the code.

It has been run-tested (as a standard forward proxy, so not all
code-paths may have been explored, but it didn't crash).

-- 
    /kinkie