Refactored alarm settings functions

- Moved this functionality into two different functions
    - check_alarms_node_presave implements hook_node_presave, and will check
      if a new alarm setting content has been created. If so, it will create
      all of the associated alarms for the next week.
    - update_alarms will, once a day, go through each alarm settings content,
      and add any alarms for 7 days from now.