virt: Allow virsh.resume to return CmdResult.

Signed-off-by: Yu Mingfei <yumingfei@cn.fujitsu.com>
virt-libvirt: Add configuration for virsh resume test.

Signed-off-by: Yu Mingfei <yumingfei@cn.fujitsu.com>
virt-libvirt: Add test module for virsh resume.

Signed-off-by: Yu Mingfei <yumingfei@cn.fujitsu.com>