* Stop setting the Name tag on a shared subnet/vpc
* Stop setting the legacy KubernetesCluster tag on a shared subnet/vpc
that is new enough (>=1.6); we rely on the shared tags instead
* Set tags on shared subnets; i.e. we _do_ set the shared tag on a
shared subnet; that is important for ELBs
* Set tags on shared VPCs; i.e. we _do_ set the shared tag on a shared
VPC; that is not used but consistent with subnets.
* Add tests for shared subnet
This lets us use the new shared cluster tags, for shared networking
objects - in particular subnets.
We continue to add the existing tags also, for compatability. When we
add direct management of shared networks, we will likely address that.
- Previous method would have caused issues with the way tags are used
for filtering resources.
- Updated docs and comments to only refer to instance groups, rather
than all AWS resources
User reports of kubelet flags not being passed; moved more to code.
Also found & fixed the likely root-cause issue: we have two copies of
the cluster spec and were not being precise about which one we wanted to
use at all times.
* Zones are now subnets
* Utility subnet is no longer part of Zone
* Bastion InstanceGroup type added instead
* Etcd clusters defined in terms of InstanceGroups, not zones
* AdminAccess split into SSHAccess & APIAccess
* Dropped unused Multizone flag