[cloudstack] add disk_offering model tests

tests/cloudstack/compute/models/disk_offering_tests.rb

@@ -0,0 +1,5 @@
+Shindo.tests("Fog::Compute[:cloudstack] | disk_offering", "cloudstack") do
+  config = compute_providers[:cloudstack]
+  compute = Fog::Compute[:cloudstack]
+  model_tests(compute.disk_offerings, config[:disk_offering_attributes], config[:mocked])
+end

tests/compute/helper.rb

@@ -67,6 +67,7 @@ def compute_providers
         :end_port => 456,
         :protocol => 'tcp'
       },
+      :disk_offering_attributes => { :name => "new disk offering", :display_text => 'New Disk Offering' },
       :mocked => true
     },
     :glesys   => {