* Don't push containers if not changed
* Do preinstall role only once and redistribute defaults to
  corresponding roles

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Signed-off-by: Chad Swenson <chadswen@gmail.com>

test to change the machine type

Revert "test to change the machine type"

This reverts commit 7a91f1b5405a39bee6cb91940b09a0b0f9d3aee1.

use google dns server when no upstream dns are defined

comment upstream_dns_servers

update documentation

remove deprecated kubelet flags

Revert "remove deprecated kubelet flags"

This reverts commit 21e3b893c896d0291c36a07d0414f4cb88b8d8ac.

and correct checksums

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Move the variable kube_version to defaults to have the possibility to overwrite it via group_vars inventory if needed.

Save/push/load containers if only download.enabled and download.container

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

"else omit" is causing problems in this expression. Replacing
it with more strict "inventory_hostname" fixes the issue and
handles `download_run_once` as expected.

Closes issue #514

* Add the retry_stagger var to tweak push and retry time strategies.
* Add large deployments related docs.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Move version/repo vars to download role.
Add container to download params, which overrides url/source_url,
if enabled.
Fix networking plugins download depending on kube_network_plugin.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Fixes #450

Nearly the last stage of source all components to containers.
Kubectl will be called from hyperkube image.

Remaining tasks:
 * Move kube_version variable to kubernetes/preinstall
 * Drop placeholder download.nothing requirement

kubelet via docker
kube-apiserver as a static pod

Fixed etcd service start to be more tolerant of slow start.

Workaround for kube_version to stay in download role, but not
download an files by creating a new "nothing" download entry.

Improves upgradability of calicoctl by leveraging docker tags.

This should make things a little more composable,
by making these roles meta roles that perform no
actions by default we allow each role to own its own
resources.

using a shared folder can cause race conditions for the download
role as it tries to download files on all the nodes to the same
shared path.  This adds a flag to run the tasks in the download
role on just one node.