Featured images v1.6 changes: Added code to identify which attachment is corrupt.
Featured images v1.5 changes: Fixed issue where on occasion a featured image would show full size.
Featured images v1.4 changes: Added height attribute to img tag.
Featured images v1.3 changes: Improved reporting if attachment is corrupt.
Featured images v1.2 changes: Added 'Limit wide' and 'Limit narrow' to options page.
Featured images v1.1 changes: No longer dependent of a specific image handler. File system operations now using XenForo file functions.
