fixed rspec dependency issue

git-svn-id: https://dev.finn.de/svn/cockpit/trunk@215 7926756e-e54e-46e6-9721-ed318f58905e

tasks/spec.rake

@@ -1,5 +1,5 @@
+begin
   require "spec/rake/spectask"
-
   namespace :spec do
     namespace :plugins do
       desc "Runs the examples for redmine_costs"
@@ -9,5 +9,6 @@ namespace :spec do
       end
     end
   end
-
   task :spec => "spec:plugins:redmine_costs"
+rescue LoadError
+end