Add runtime-tools' validation tests

[alban]

For now, the results of the tests are printed without returning an error.

Signed-off-by: Alban Crequy alban@kinvolk.io

---

This is similar to opencontainers/runc#1758. But here I get this error:

writing file
'/sys/fs/cgroup/cpu,cpuacct/system.slice/libcrun-58f278ec-efa5-4587-bfb5-63b77347b69a/cgroup.procs':
No space left on device

I don't know what is this error but it reminds me of a bug in the kernel fixed in Linux 4.2 and a bug in Docker fixed in Docker 1.8 (see also opencontainers/runc#133 and rkt/rkt#1210).

[giuseppe]

thanks for the PR, I am going to take a look at the failure

[giuseppe]

@alban I've pushed a fix for the error you reported here: giuseppe@fa4991a