didTapSubmit.swift

 @IBAction func didTapSubmit(_ sender: UIButton) {
        // Get properties for the unicorn-to-be-created
        let addedBy = self.addedBy.text ?? ""
        let seenAt = self.seenAt.text ?? ""
        let unicorn = Unicorn(imagePath: storageImagePath, addedBy: addedBy, seenAt: seenAt)

        // Create the unicorn and record it
        writeUnicornToDatabase(unicorn)

        // Return to Unicorns Table VC
        navigationController?.popViewController(animated: true)
    }