Improvement: The "Preview Popup" button has been removed from the top admin bar. It wasn't working on any page other than the extension's own settings page, and that page already has a dedicated button anyway.
Fix: The popup preview could be seen by any logged in user.
Fix: Typo on settings page.
Fix: Update docs link to use https.
Refactor: Change plugin author name to "Sandhills Development, LLC".
Dev: EDD 3.0 compatibility.
