Update ulimit modules to support Red Hat.

Adds a new params module which is used to provide distribution
specific parameters for other modules. The init module was updated
to make use of the new parameters.

Change-Id: Ib81e919a777741d9d58d687672508b8dd53498ff
Reviewed-on: https://review.openstack.org/18997
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Reviewed-by: James E. Blair <corvus@inaugust.com>
Approved: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins

manifests/init.pp

@@ -2,7 +2,9 @@
 #
 class ulimit {
 
-  package { ['libpam-modules', 'libpam-modules-bin']:
+  include ulimit::params
+
+  package { $::ulimit::params::pam_packages:
     ensure => present,
   }
 
@@ -11,4 +13,5 @@ class ulimit {
     owner  => 'root',
     mode   => '0755',
   }
+
 }

manifests/params.pp

@@ -0,0 +1,17 @@
+# Class: ulimit::params
+#
+# This class holds parameters that need to be
+# accessed by other classes.
+class ulimit::params {
+  case $::osfamily {
+    'Fedora', 'Redhat': {
+      $pam_packages = ['pam']
+    }
+    'Debian', 'Ubuntu': {
+      $pam_packages = ['libpam-modules', 'libpam-modules-bin']
+    }
+    default: {
+      fail("Unsupported osfamily: ${::osfamily} The 'ulimit' module only supports osfamily Fedora, Redhat, Debian, or Ubuntu.")
+    }
+  }
+}