added FreeBSD 10 CARP support and few improvements

I've added FreeBSD 10 CARP support with "vhid123" in ether address, which uses the if_carp.c calculated MAC (00:00:0e:00:01:<HEX_VHID>). You can check it in https://github.com/freebsd/freebsd/blob/master/sys/netinet/ip_carp.c#L1440.

Removed few warnings generated in OpenBSD and FreeBSD and translated some magic numbers.