MetalK8s 1.1.0-alpha1

This is a preview release of MetalK8s 1.1.0. Among many changes, this updates the Kubernetes cluster to version 1.11.3.

Other changes include:

• The ability to override Helm chart configurations ('values') of several charts deployed with MetalK8s
• More platform checks during deployment
• Updates of various services and dashboards deployed as part of the cluster
• Increased memory limits for etcd on low-resource servers
• Various bug-fixes

See the Changes section in the reference guide, or ChangeLog.rst for an exhaustive listing.