[PATCH] Start use capabilities on linux

[Rush]

This is not nginx-ENG at sysoev.ru mail list, here is nginx-RU at sysoev.ru :)

Kirill A. Korinskiy пишет:
> From: Kirill A. Korinskiy <catap at catap.ru>
>
> The nginx required privilege mode only on master process and only bind
> ports <1024. In linux proccess can bind ports <1024 in not privilege
> mode if the process does capset(CAP_NET_BIND_SERVICE).
>