GroundZero 0.6.0: cluster mode

Cluster mode: servers named after their BMC, addresses from a pool, and an optional DNS check.

Added

• Clusters: an ESXi config set, an IP range, a DNS domain and a naming rule (/clusters).
  • Adding a server names it after its BMC (prefix or suffix stripped, e.g. idrac-esx01 becomes esx01)
    and gives it the next free address in the range. Both are written as its per-host values.
  • Inventory now reads the BMC's own hostname.
• Verify DNS: asks the cluster's own DNS servers (never the local resolver) for the forward and reverse
  records and names what does not match.
  • It is an option. A cluster with "Require a passing DNS check before install" set blocks its members'
    OS install until it passes; skip_dns_check overrides that.
• UI: a Clusters page with members, derived names and addresses, DNS status and Verify DNS.
• Simulator: a configurable BMC hostname and a static DNS map.