update to v1.4.0

NVR: docker-io-1.4.0

- Resolves: rhbz#1173325
- Resolves: rhbz#1172761 - CVE-2014-9356
- Resolves: rhbz#1172782 - CVE-2014-9357
- Resolves: rhbz#1172787 - CVE-2014-9358
- update to upstream v1.4.0
- override DOCKER_CERT_PATH in sysconfig instead of patching the source
- update metaprovides
- define PR_SET_CHILD_SUBREAPER as per newer kernel-headers

Signed-off-by: Lokesh Mandvekar <lsm5@fedoraproject.org>