check explicitly if hostmanager.ignore_private_ip is set to true

[nagas]

As vagrant hostmanager (in contrary to eg. vagrant provision) doesn't implicate config finalization and validation, hostmanager.ignore_private_ip is never set to false in such a case. It is just an object

class Config
# [...]
  UNSET_VALUE = Object.new

and the below statement

unless machine.config.hostmanager.ignore_private_ip

results in false, causing the plugin to ignore private ip when the option is not set at all.

It would be probably better to force vagrant hostmanager to finalize! and validate the configuration, but I couldn't figure it out yet.

[smdahlen]

Thanks for PR. I'll go ahead and merge. With the regards to config validation, I have that on my list to do. The command needs to call an action stack using the action runner with ConfigValidate included.