Windows port merge - pinger and IPPROTO [PATCH]

Hi,

This is the 5th of some splitted native Windows patches grouped by
functionality.

Native Windows port enhancements:

- Added native Windows and Cygwin support to pinger.cc
- Introduced the use of IPPROTO_TCP and IPPROTO_UDP defines instead of '0'
on comm_open, needed by Winsocket. See this old squid-dev thread about:
http://www.squid-cache.org/mail-archive/squid-dev/200108/0162.html

Regards

Guido

-
=======================================================
Serassio Guido
Via Albenga, 11/4 10134 - Torino - ITALY
E-mail: guido.serassio@serassio.it
WWW: http://www.serassio.it