libct: handle mounts

Signed-off-by: Andrey Vagin <avagin@openvz.org>
libct: handle network

Signed-off-by: Andrey Vagin <avagin@openvz.org>
libct: submodule

Signed-off-by: Andrey Vagin <avagin@openvz.org>
linux: fix tests

Signed-off-by: Andrey Vagin <avagin@openvz.org>
travis: sudo: false

Signed-off-by: Andrey Vagin <avagin@openvz.org>