doc: Document all the new network config keys
doc: Document all the new network config keys

Signed-off-by: Stéphane Graber <089afc6d81f66f1168a9849e15660feae286e024@ubuntu.com>

hallyn/lxd,lxc/lxd,atxwebs/lxd,ollie314/lxd,erikmack/lxd,stgraber/lxd,georghopp/lxd,stgraber/lxd,stgraber/lxd,chrisglass/lxd,stgraber/lxd,hallyn/lxd,akshaykarle/lxd,techtonik/lxd,jsavikko/lxd,pcdummy/lxd,erikmack/lxd,akshaykarle/lxd,hallyn/lxd,stgraber/lxd,erikmack/lxd,hallyn/lxd,Skarlso/lxd,lxc/lxd,lxc/lxd,stgraber/lxd,mjeanson/lxd,stgraber/lxd,chrisglass/lxd,lxc/lxd,pcdummy/lxd,jsavikko/lxd,pcdummy/lxd,atxwebs/lxd,Skarlso/lxd,lxc/lxd,chrisglass/lxd,atxwebs/lxd,jsavikko/lxd,Skarlso/lxd,lxc/lxd,lxc/lxd,georghopp/lxd,atxwebs/lxd,mjeanson/lxd,Skarlso/lxd,georghopp/lxd,ollie314/lxd,mjeanson/lxd,akshaykarle/lxd,hallyn/lxd,techtonik/lxd,techtonik/lxd,ollie314/lxd,hallyn/lxd