This commit rearranges the CSV errors (again) to make them geared towards
teaching you how to match placeholders to the column headers.
So the order of errors now is:
1. No phone number/email column
2. Column headers don’t match placeholders
3. Missing or bad data
4. Trial mode
5. Daily limit reached
This depends on:
- [x] https://github.com/alphagov/notifications-utils/pull/39 for 1.