Make downloaded images private by default
Make downloaded images private by default

Automatically cached images should be private and copied images should
only be public if the user passes --public.

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

ollie314/lxd,lxc/lxd,lxc/lxd,yura-pakhuchiy/lxd,pcdummy/lxd,lxc/lxd,techtonik/lxd,ericsnowcurrently/lxd,mjeanson/lxd,georghopp/lxd,atxwebs/lxd,mjeanson/lxd,lxc/lxd,stgraber/lxd,Skarlso/lxd,mjeanson/lxd,stgraber/lxd,dustinkirkland/lxd,ericsnowcurrently/lxd,georghopp/lxd,akshaykarle/lxd,lxc/lxd,atxwebs/lxd,techtonik/lxd,stgraber/lxd,stgraber/lxd,Skarlso/lxd,yura-pakhuchiy/lxd,Skarlso/lxd,erikmack/lxd,ericsnowcurrently/lxd,chrisglass/lxd,Malizor/lxd,jsavikko/lxd,yura-pakhuchiy/lxd,akshaykarle/lxd,lxc/lxd,pcdummy/lxd,jsavikko/lxd,pcdummy/lxd,hallyn/lxd,hallyn/lxd,chrisglass/lxd,hallyn/lxd,ollie314/lxd,techtonik/lxd,Malizor/lxd,atxwebs/lxd,georghopp/lxd,stgraber/lxd,stgraber/lxd,jsavikko/lxd,chrisglass/lxd,atxwebs/lxd,Malizor/lxd,akshaykarle/lxd,erikmack/lxd,Skarlso/lxd,dustinkirkland/lxd,dustinkirkland/lxd,hallyn/lxd,hallyn/lxd,lxc/lxd,erikmack/lxd,stgraber/lxd,hallyn/lxd,ollie314/lxd