net.c 1.07 | main.c 1.03 | net.h v 1.04 (Add support for both IPv4 and IPv6)

Add support for both IPv4 and IPv6, host and client.
1. Add IPv6 support mark flag: IPv6
(set to 1 if support, otherwise set to 0)
2. Ipcheck() function can check both ipv4 and ipv6 validation since this
version.
3. Add support for IPv6--Client Info
4. Add support for IPv6--Host.
Support for binding IPv6 address to host.
5. Add host_ipv6 flag.
Default by 0.