Prefetching postconf provider instances fails if not all entries are managed by puppet

[oxc]

In my setup, I'd like to only have those config parameters in my main.cf that I have explicitly defined in puppet.

Thanks to the resource provider, this could usually be achieved by this snippet:

resources { 'postconf': 
  purge => true,
  noop => true, # only warn about unmanaged resources
}

However, this fails with a Nil dereference in postconf.rb#L42, where the value is split unless size==1, because those resources have no value set.

I tried to fix this and submit a pull request, but I can't really figure out what's going on here in the first place. Can you explain why the value is split on /', +/? Seems strange :) (Note that there are postconf values that can legally contain a comma followed by a space which does not donate multiple values, e.g. in the subkey syntax for smtpd_milters)
If I change the unless condition to handle nil values (either way), or remove the split altogether, everything seems to work correctly.

[oxc]

See #5