* * add or-operator and a simlple unit test for hw_address, ip_address, ipv6_address
* add not-operator and a simlple unit test for hw_address, ip_address, ipv6_address
* add greater-then-operator and a simlple unit test for ipv6_address
* add new constructor and a simlple unit test for network_interface, which use a ipv6_address to find the nic
* add override the function gateway_from_ip for ipv6_address parameter (untested)
* change the ipv6_address in NotMaskAdress_Test, so that the expceted addresses are valid for the winsock api
* Delete CMakeLists.txt.user
* * add <=, >, >= operator for HWAddress with tests
* add <=, >, >= operator for IPv4Address with tests
* add <=,>= operator for IPv6Address with tests
* refactoring the & , |, ~ operator of ipv6_address to "regular" operator
