I considered using the vine error message as the translation key (ie I18n.t(vine_voucher_validator_service.errors.#{message.parameterize.underscore}), but thought it might be more predictable to have keys explicitly defined and whitelisted like this.
These error message are still squashed by the controller, we'll deal with that next.
Rails 4.1 added time helpers but we never bothered using them. But now
I'm getting rid of the Timecop dependency and use standard helpers.
Beware though that the new helpers always freeze time. When you travel
to a certain date then the clock stops ticking while Timecop maintained
the passing of time.
The freezing of time could cause problems if you are trying to enforce a
timeout. But all current specs don't seem affected.
In most cases, the freezing will make it easier to avoid flaky specs.
