delay sensu_service_trigger notifcations from json_file resources
delay sensu_service_trigger notification from package[sensu] resource
define sensu_path method which returns sensu install prefix and update other methods to use it
move sensu runit enable sequence into sensu_service lwrp
avoid CHEF-3694 warnings via class instance var
Merge pull request #203 from needle-cookbooks/delay-json-file-service-notifications

Delay notifications from json_file resources sent to sensu_service_trigger
Merge pull request #205 from needle-cookbooks/sensu_service-cleanup

DRY up CHEF-3694 warnings and more