cgroup.cgroup: Change setup to initialize

Setup is called only once to unzip/compile projects. Cgroups needs
to be initialized each time it's executed so it shoule use
initialize() instead.

Signed-off-by: Lukáš Doktor <ldoktor@redhat.com>
cgroup: add memory subsystem test

Signed-off-by: Li Yang <liyang.fnst@cn.fujitsu.com>