Update the release script
Update the release script

Updates the release script with SHA256 sums, installation guide as well
as a switch to kubernetes from kubernetes-incubator.

procrypt/kompose,rupalibehera/kompose,kadel/kompose,kubernetes/kompose,cdrage/kompose,rupalibehera/kompose,skippbox/kompose,procrypt/kompose,rupalibehera/kompose,cdrage/kompose,skippbox/kompose,surajnarwade/kompose,skippbox/kompose,surajnarwade/kompose,ashetty1/kompose,kadel/kompose,procrypt/kompose,kubernetes/kompose,ashetty1/kompose,surajnarwade/kompose,ashetty1/kompose