FluentSMTP 2.2.1

• Refactored Google API integration
• Fix encoding issues for Outlook API connection
• ElasticMail Attachment issues fixed
• Fixed digest email esc_* issues
• Added contributors to the plugin about page.
• UI&UX Improvements

Special thanks to our contributors in the version:

@MikSco
@razorfrog
@Brugman
@saberg3