support optional environment attribute in services to filter services by environment
support optional environment attribute in unmanaged hosts data bag
Update README for environment filters on services and unmanaged hosts
rebase branch from master
support optional environment attribute in unmanaged hosts data bag
Update README for environment filters on services and unmanaged hosts
Merge branch 'environment-filters' of github.com:jwilf/nagios into environment-filters

Conflicts:
	templates/default/services.cfg.erb
Merge pull request #203 from jwilf/environment-filters

[COOK-3774] Environment filters