CB-10631 ios: Fix for device.uuid in iOS 5.1.1
CB-10631 ios: Fix for device.uuid in iOS 5.1.1

- Check if identifierForVendor exists and if not create a new UUID
  and store in on the device for future use.

purplecabbage/cordova-plugin-device,apache/cordova-plugin-device,purplecabbage/cordova-plugin-device,purplecabbage/cordova-plugin-device,apache/cordova-plugin-device,purplecabbage/cordova-plugin-device