IPv6: add copy about why INET could not just be upgraded
IPv6: add copy about why INET could not just be upgraded

autarch/perlweb,briandfoy/perlweb,autarch/perlweb,ajolma/perlweb,briandfoy/perlweb,bjakubski/perlweb,alcy/perlweb,dagolden/perlweb,dagolden/perlweb,ajolma/perlweb,alcy/perlweb,PeterMartini/perlweb,PeterMartini/perlweb,briandfoy/perlweb,PeterMartini/perlweb,ajolma/perlweb,alcy/perlweb,Abigail/perlweb,dagolden/perlweb,autarch/perlweb,Abigail/perlweb,bjakubski/perlweb,bjakubski/perlweb,Abigail/perlweb