builder/vmware-esxi: Ignore localhost for VNC lookup [GH-1480]

  Adds logic to ESXi driver VNC Address function to ignore listen
  addresses that bind to localhost (127.0.0.1), this allows certain
  default ports to be available on ESXi for VNC connections
website: document vmware-esxi VNC requirements
Merge pull request #1505 from jasonberanek/issue-1480

builder/vmware-esx: Ignore localhost for VNC lookup and document VNC requirements [GH-1480]