Reproducible compression
Reproducible compression

With this, multiple publicaton of the same unchanged container or
snapshot will lead to the same hash.

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

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