Fix Sensu Enterprise services when not using enterprise

[Pryz]

When using the current master with the Sensu (not enterprise), I'm getting :

Notice: /Stage[main]/Sensu::Api::Service/Service[sensu-api]: Triggered 'refresh' from 1 events
Notice: /Stage[main]/Sensu::Server::Service/Service[sensu-server]: Triggered 'refresh' from 1 events
Error: /Stage[main]/Sensu::Enterprise::Service/Service[sensu-enterprise]: Could not evaluate: Could not find init script or upstart conf file for 'sensu-enterprise'
Error: /Stage[main]/Sensu::Enterprise::Service/Service[sensu-enterprise]: Failed to call refresh: Could not find init script or upstart conf file for 'sensu-enterprise'
Error: /Stage[main]/Sensu::Enterprise::Service/Service[sensu-enterprise]: Could not find init script or upstart conf file for 'sensu-enterprise'
Notice: /Stage[main]/Sensu::Enterprise::Dashboard/Anchor[sensu::enterprise::dashboard::begin]: Dependency Service[sensu-enterprise] has failures: true
Warning: /Stage[main]/Sensu::Enterprise::Dashboard/Anchor[sensu::enterprise::dashboard::begin]: Skipping because of failed dependencies
Notice: /Package[sensu-enterprise-dashboard]: Dependency Service[sensu-enterprise] has failures: true
Warning: /Package[sensu-enterprise-dashboard]: Skipping because of failed dependencies
Notice: /Stage[main]/Sensu::Enterprise::Dashboard::Config/File[/etc/sensu/dashboard.json]: Dependency Service[sensu-enterprise] has failures: true
Warning: /Stage[main]/Sensu::Enterprise::Dashboard::Config/File[/etc/sensu/dashboard.json]: Skipping because of failed dependencies
...
Notice: /Stage[main]/Sensu::Enterprise::Dashboard::Service/Service[sensu-enterprise-dashboard]: Dependency Service[sensu-enterprise] has failures: true
Warning: /Stage[main]/Sensu::Enterprise::Dashboard::Service/Service[sensu-enterprise-dashboard]: Skipping because of failed dependencies
Error: /Stage[main]/Sensu::Enterprise::Dashboard::Service/Service[sensu-enterprise-dashboard]: Failed to call refresh: Could not find init script or upstart conf file for 'sensu-enterprise-dashboard'
Error: /Stage[main]/Sensu::Enterprise::Dashboard::Service/Service[sensu-enterprise-dashboard]: Could not find init script or upstart conf file for 'sensu-enterprise-dashboard'

This pull request fixes the issue by changing the if and the case in each service.pp for the Enterprise version. I also changed a little bit the rspec tests.