build: Don't package derived ks

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
build: Add example for installing a rootfs

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
test: Disabling packaging check

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>
test: Add parallelism to travis

Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>