nrpe config files should not be world readable as they can contain sensitive info like passwords, keys, etc.
Correct the IP check logic to check the right node

I had it checking the Nagios server's attributes before when I wanted
the search discovered node
Don't fail to write out services in the hostgroups databags

Fix the logic for checking for valid host groups
[COOK-2565] Update nginx.conf.erb for correct use AUTH
Merge pull request #140 from tas50/COOK-2257

COOK-2257: Correct the IP check logic to check the right node
[COOK-2474] don't assume node has cloud attributes

Prior to this the cookbook assumed if the server node had a cloud
attributes, every node had the cloud attributes, this removes this
assumption.
Merge branch 'COOK-2474'
Merge pull request #141 from tas50/COOK-2558

COOK-2558: Don't fail to write out services in the hostgroups databags
Merge pull request #139 from scottso/fix_config_perms

[COOK-2546] nrpe config files should not be world readable
Merge pull request #143 from pioneerit/COOK-2565

[COOK-2565] Update nginx.conf.erb for correct use AUTH
[COOK-2546] - use nagios user/group attribute