WPForms Basic 1.9.2.1

### Fixed
- Some smart tags are not rendered correctly in the email notifications if sent asynchronously.

### Fixed
- Checkbox image click doesn't work well to select an option.
- Do not allow empty connection names (spaces only) for providers.
- File Upload field: properly handle `{field_value_id="#"}` smart tag.
- Provide proper defaults to Date / Time field, when only Date or only Time format is selected.

### IMPORTANT
- Support for PHP 5.4 has been discontinued. If you are running PHP 5.4, you MUST upgrade PHP before installing WPForms 1.5.9. Failure to do that will disable WPForms core functionality.