added logic to handle single email for a single threshold breached + costIntervalStart combination

[srinises]

• Added a sample of the JSON file that is used to validate if an email was sent previously

• Created file cloud_storage_interact.js to implement the logic to

  • check if a file of the format "projectName_budgetAlertSent.json" exists in the storage bucket
  • Create it if it doesn't using the sample format
  • check if the email was previously sent for the threshold + costIntervalStart combination
  • set a boolean variable sendEmail value based on the above determination
  • return a Json object that contains a boolean value sendEmail and a string value alertEmailSentAt

• Updated package.json

[seanpoulter-foci]

Thanks @srinises. I'm reworking this try to handle the race conditions and not hard code the threshold values.