Correct the issue - COOK-3136

http://tickets.opscode.com/browse/COOK-3136
Ensure that the length of the htpasswd string is > 0 (see COOK-3140)
Fix syntax error
Simply platform check logic for nginx install to catch all RHEL 5 versions
Clean up syntax per jtimberman
Merge pull request #164 from pierreozoux/COOK-3136

Correct the issue - COOK-3136
Merge pull request #165 from stormerider/COOK-3140

Fix htpasswd.users template to only create users who have htpasswd field set
Merge pull request #167 from tas50/COOK-2891

COOK-2891: Simply platform check logic for nginx install to catch all RHEL 5 versions
Utilize the host_name_attribute when writing out hostgroups from nagios_hostgroups
Merge pull request #170 from zippykid/COOK-3282

COOK-3282: Utilize the host_name_attribute when writing out hostgroups from nagios_hostgroups