travis: don't run cgroup tests

Travis uses cpusets in such a way [1] that we can't actually write to
cpuset.cpu_exclusive ever, so none of these tests will work. They'll still
work in jenkins, though, so disabling them is probably ok.

Closes #118

[1]: https://github.com/travis-ci/worker/blob/master/backend/docker.go#L66Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
CC: Andrew Vagin <avagin@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

scripts/travis-tests

@@ -8,4 +8,4 @@ apt-get install -qq protobuf-c-compiler libprotobuf-c0-dev libaio-dev libprotobu
 chmod a+x $HOME
 make
 make -C test/zdtm
-python test/zdtm.py run -a -f h,ns
+python test/zdtm.py run -a -f h,ns -x 'cgroup*'