sensu::check notifies the server even when not running the service

[ripienaar]

https://github.com/sensu/sensu-puppet/blob/master/manifests/check.pp#L119 will notify the sensu::server::service class whenever a check changes.

The sensu::server::service class will correctly set ensure and enable but when notifying the class puppet will log confusing lines:

Notice: /Stage[main]/Sensu::Server::Service/Service[sensu-server]: Triggered 'refresh' from 1 events

when in fact what it's doing is the right thing, it notices that the service is stopped and does not restart it:

Debug: Executing '/etc/init.d/sensu-api status'
Debug: Service[sensu-server](provider=upstart): Could not find sensu-server.conf in /etc/init
Debug: Service[sensu-server](provider=upstart): Could not find sensu-server.conf in /etc/init.d
Debug: Service[sensu-server](provider=upstart): Could not find sensu-server in /etc/init
Debug: Executing '/etc/init.d/sensu-server status'
Debug: Executing '/etc/init.d/sensu-server status'
Debug: /Stage[main]/Sensu::Server::Service/Service[sensu-server]: Skipping restart; service is not running
Notice: /Stage[main]/Sensu::Server::Service/Service[sensu-server]: Triggered 'refresh' from 1 events

To avoid the confusing message I think the server::service class should only be notified if $sensu::server is true

[jlambert121]

@ripienaar Does #190 work for you? There is likely a more elegant way of doing that I'm not aware of too.