Added support for RHEL and did some syntax cleaning

Assume that "RedHat" also works where "CentOS" does.

custom/manifests/init.pp

@@ -5,7 +5,7 @@ class custom {
         ensure => directory,
         mode   => "0755",
         owner  => root,
-        group  => $operatingsystem ? {
+        group  => $::operatingsystem ? {
             OpenBSD => wheel,
             default => root,
         },
@@ -121,7 +121,7 @@ class custom::rootpassword {
         fail("Root password hash not defined.")
     }
 
-    case $operatingsystem {
+    case $::operatingsystem {
         openbsd: {
             exec { "usermod -p \${SECRET} root":
                 environment => "SECRET=${root_password}",