start workers as root

start workers as root

SMP workers in trunk start without root privileges. This results in startup
failures when workers need to use a privileged port (e.g., 443) or other
root-only features such as TPROXY.

The watch_child function, responsible to watch and start squid workers for
the squid monitor process, called after a enter_suid() call, but the
writePidFile() call, inside the watch_child(), will leave suid mode before exit.

This patch add enter_suid() cals after the writePidFile and removePidFile()
inside the watch_child() function.

This is a Measurement Factory project