* Fixed: Add download_count meta to versions
* Changed: Setting default version names to imported versions without name. * Added: Thumbnail( featured image ) import. * Added: Activation/Deactivation hooks for license * Changed: Populate published date from CSV column
* Changed: Notices priority set to 8. * Fixed: Fix for PHP 5.6 error "unexpected '::' (T_PAAMAYIM_NEKUDOTAYIM)".
