v1.22.0
* New feature: "Messages" tab in Edit Form screen allows for complete language customization.
* New feature: "Prefill" control for setting a default value on Short Text, Long Text, Email Address and Number fields.
* New feature: "Hide button to go to previous page" for preventing users from stepping backwards in multi-page forms.
* Improvement: File Uploads of incomplete submissions are now hidden then removed to protect privacy.
* Improvement: Mailchimp integration now updates existing subscriber's data.
* Bugfix: "Email respondent a copy of their submission" → "Include submitted" feature was misbehaving.
* Bugfix: PDF rendering of quotes was generating bad values.
* Bugfix: Zapier integration was pushing wrong values for optional File Upload fields
