[PATCH 1 of 3] Added support for trailers in HTTP responses

[Piotr Sikora]

Hey Maxim,

> I've tried this as well, and decided that "if (len ==
> sizeof(...))" is slightly more readable, and also produces smaller
> patch to your code.   No strict preference though, feel free to
> use any variant you think is better.

I've ended up using "if (len == 0) { ... }" in the end, but applied
rest of you changes. Thanks!

Best regards,
Piotr Sikora