allow untrusted images get
allow untrusted images get

The imagesGet function knows to only hand public images over,
and this is a key feature of the lxd images server.

Signed-off-by: Serge Hallyn <3df611b026e4639bee8aef7a4beb2e39fcebb313@ubuntu.com>

achanda/lxd,georghopp/lxd,dvbportal/osx-lxd,lxc/lxd,stgraber/lxd,mikemccracken/lxd,jumpstarter-io/lxd,Skarlso/lxd,jsavikko/lxd,hallyn/lxd,benaryorg/lxd,jsavikko/lxd,dustinkirkland/lxd,ericsnowcurrently/lxd,ericsnowcurrently/lxd,mjeanson/lxd,erikmack/lxd,atxwebs/lxd,stgraber/lxd,hallyn/lxd,dustinkirkland/lxd,smoser/lxd,lxc/lxd,rcj4747/lxd,stgraber/lxd,ollie314/lxd,smoser/lxd,benaryorg/lxd,atxwebs/lxd,jensg-st/lxd,chrisglass/lxd,mjeanson/lxd,beni55/lxd,beni55/lxd,hallyn/lxd,Malizor/lxd,rcj4747/lxd,lxc/lxd,rrva/lxd,stgraber/lxd,pcdummy/lxd,sl1pm4t/lxd,mjeanson/lxd,atxwebs/lxd,chrisglass/lxd,ericsnowcurrently/lxd,lxc/lxd,Malizor/lxd,pcdummy/lxd,lxc/lxd,erikmack/lxd,jensg-st/lxd,hallyn/lxd,stgraber/lxd,beni55/lxd,benaryorg/lxd,akshaykarle/lxd,akshaykarle/lxd,sl1pm4t/lxd,Skarlso/lxd,Skarlso/lxd,sl1pm4t/lxd,mikemccracken/lxd,georghopp/lxd,techtonik/lxd,achanda/lxd,yura-pakhuchiy/lxd,akshaykarle/lxd,techtonik/lxd,hallyn/lxd,stgraber/lxd,mikemccracken/lxd,achanda/lxd,lxc/lxd,smoser/lxd,techtonik/lxd,ollie314/lxd,chrisglass/lxd,hallyn/lxd,jumpstarter-io/lxd,georghopp/lxd,atxwebs/lxd,dvbportal/osx-lxd,jumpstarter-io/lxd,erikmack/lxd,ollie314/lxd,rcj4747/lxd,pcdummy/lxd,yura-pakhuchiy/lxd,dustinkirkland/lxd,jensg-st/lxd,rrva/lxd,rrva/lxd,Skarlso/lxd,yura-pakhuchiy/lxd,jsavikko/lxd,dvbportal/osx-lxd,lxc/lxd,stgraber/lxd,Malizor/lxd