Revised code rather heavily:

Revised code rather heavily:
 - Changed Router Advertisements from /64 to /114 prefix
 - Modified old port/address code with ^0x02 bit flipping
 - Unicast ICMPv6 replies are now sent to the original requester
 - validate_originator() is tightened somewhat, but questions remain
 - Still several places where a brusque assumption of a /64 is made