test/storage: add tests using btrfs on LVM and ceph volumes
test/storage: add tests using btrfs on LVM and ceph volumes

Signed-off-by: Alberto Donato <3d6ca22374542c32836b344db03c69e81292ccc8@canonical.com>

Skarlso/lxd,pcdummy/lxd,mjeanson/lxd,lxc/lxd,stgraber/lxd,atxwebs/lxd,Skarlso/lxd,jsavikko/lxd,lxc/lxd,Skarlso/lxd,atxwebs/lxd,lxc/lxd,erikmack/lxd,erikmack/lxd,hallyn/lxd,jsavikko/lxd,hallyn/lxd,lxc/lxd,jsavikko/lxd,mjeanson/lxd,hallyn/lxd,stgraber/lxd,stgraber/lxd,hallyn/lxd,stgraber/lxd,atxwebs/lxd,pcdummy/lxd,erikmack/lxd,Skarlso/lxd,lxc/lxd,stgraber/lxd,lxc/lxd,stgraber/lxd,hallyn/lxd,mjeanson/lxd,hallyn/lxd,pcdummy/lxd,stgraber/lxd,atxwebs/lxd,lxc/lxd