add a separate datatype for servicedefault

Needed for non String types if they have a default
that points to facts['os_service_default'].
Otherwise we need to allow String for all parameters.

Since the function is_service_default checks the string,
I do not assume that the fact is overwritten in
any deployment !

Change-Id: Ic2b969f9b99d1748c80edb691f38f4451e499a80

spec/type_aliases/servicedefault_spec.rb

@@ -0,0 +1,33 @@
+require 'spec_helper'
+
+describe 'Openstacklib::ServiceDefault' do
+  describe 'valid types' do
+    context 'with valid types' do
+      [
+        '<SERVICE DEFAULT>',
+      ].each do |value|
+        describe value.inspect do
+          it { is_expected.to allow_value(value) }
+        end
+      end
+    end
+  end
+
+  describe 'invalid types' do
+    context 'with garbage inputs' do
+      [
+        'somethink',
+        true,
+        nil,
+        {},
+        '',
+        55555,
+      ].each do |value|
+        describe value.inspect do
+          it { is_expected.not_to allow_value(value) }
+        end
+      end
+    end
+  end
+end
+

types/servicedefault.pp

@@ -0,0 +1 @@
+type Openstacklib::ServiceDefault = Enum['<SERVICE DEFAULT>']