Convert virtcontainers tests to testify/assert to make the virtcontainers
tests more readable.
fixes#156
Signed-off-by: Julio Montes <julio.montes@intel.com>
Set new persist storage driver "virtcontainers/persist/" as "experimental"
feature.
One day when this can fully work and we're ready to move to 2.0, we'll move
it from "experimental" feature to formal feature.
At that time, the "virtcontainers/filesystem_resource_storage.go" can be removed
completely.
Signed-off-by: Wei Zhang <zhangwei555@huawei.com>