Fix possible problems with legacy calicoctl

Add document outlining upgrade process

Force hardlink for calico/canal certs

Fixes: #669

Change GCE sysctls placement and docs

Override GCE sysctl in /etc/sysctl.d/99-sysctl.conf instead of
the /etc/sysctl.d/11-gce-network-security.conf. It is recreated
by GCE, f.e. if gcloud CLI invokes some security related changes,
thus losing customizations we want to be persistent.

Update cloud providers firewall requirements in calico docs.

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

add cluster-signing to kube-controller-manager

When running legacy calicoctl we do not specify calico hostname in
calico-node container thus we should not specify it in CNI config.

Also move 'legacy_calicoctl' set_fact task to the top.

kube-controller-manager's cluster signing cert and key points by default to not
existing `/etc/kubernetes/ca/ca.pem` and `/etc/kubernetes/ca/ca.key` [docs][1]

[1]: http://kubernetes.io/docs/admin/kube-controller-manager/#options

Docker Options Refactor

Calico: fix peering with routers for new version

add restart flag for docker run kubelet

In new `calicoctl` version nodes peering with routers is broken.
We need to use predictable node names for calico-node and the
same names in calico `bgpPeer` resources and CNI.

Re-enable debian-8-kubespray image for CI

debian-8 image is missing memory cgroup, so it can't spawn pods.

Update calico-node systemd unit

GlusterFS server separate nodes and client facilities for k8s nodes.

New calicoctl does not support --detach=false option, so we should
use a recommended way to run calico-node service:
http://docs.projectcalico.org/v2.0/usage/configuration/as-service

Closes #674, #675

Add dbus socket dir to kube-proxy

Fix ipv4 forwarding on GCE

ipv4 forwarding gets broken when restarting networking, which
breaks all networking for all pods.

Update README: kargo-golang, slack, and travis urls

Fail all nodes on error

Disable logs upload and verbose logging

In order to speed up CI jobs, do not produce -v logs.
Also, disable collecting and uploading logs to GS, unless
the buckets creation issue resolved.

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

Set proxy_timeout to 10m in nginx.conf

Reduce CI test matrix

Reduce the test cases from 15 to 9, bearing in mind that:
* Disable weave/coreos gate unless its deployment fixed
* If debian/centos7 fails with net plugin X, ubuntu-xenial/rhel-7 will
  likely fail as well
* Canal also covers the flannel plugin deployment, but keep at least one
  of the flannel plugin deployment, unless it's superseded and removed.
* Keep at least one of each OS/plugin family to be tested in the separate
  nodes layout
* Keep at least one of each OS family to be tested against each of the
  plugin types in default nodes layout
* Rebalance GCE regions for instances, replace asia to eu/us as they
  are the longest running jobs.

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

add  azure support for kargo

Switch to standard debian/centos/rhel for CI