dhcp6s enable/disable from GUI

Hi Eric,

Commit 2a0d2168e331d33a251cb49025857983ee614426 has the dhcp6s enable/disable from gui 'add on'.  Unfortunately I also upgraded dnsmasq as well and don't appear to be able to split out certain commits to send to you - hopefully you can split them out, presumably 'cherry pick'.  Sorry.  Still new to this git/github stuff.  There must be a better way, perhaps if I create a 'work' branch and a 'for eric' branch and merge only the commits I want you to see?

Kevin