Update quickstart to point to kubernetes 0.15 and v1beta3 manifests

[Dane LeBlanc]

The dev quickstart document needs to be updated to point to the Kubernetes 0.15.0 release for cloning.
It also needs to be updated to point to the v1beta3 manifest for the redis pod-create example.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/191102

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/191102
Committed: https://git.openstack.org/cgit/openstack/magnum/commit/?id=a52d01528c52069138dfe9f958b9dd3492dd8c90
Submitter: Jenkins
Branch: master

commit a52d01528c52069138dfe9f958b9dd3492dd8c90
Author: Dane LeBlanc <email address hidden>
Date: Fri Jun 12 10:48:34 2015 -0400

    Update quickstart to point to kubernetes 0.15 and v1beta3 manifest

    The dev quickstart document needs to be updated to point to the
    Kubernetes 0.15.0 release for cloning. The quickstart document also
    needs to be updated to point to the v1beta3 manifest for the redis
    pod-create example.

    Change-Id: Ibf50e6a93ee0f57c82be4117aaf0aae48c339a85
    Closes-Bug: #1464689