Add BGP route reflectors support in order to optimize BGP topology
for deployments with Calico network plugin.

Also bump version of calico/ctl for some bug fixes.

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>

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.

This patch introduce `calico_network_backend` global variable,
which allow to describe alternative network backend.
Default behavior is unchanged.

Since version 'v1.0.0-beta' calicoctl is written
in Go and its API differs from old Python based
utility. Added support of both old and new version
of the utility.