Merge pull request #1 from pemaxim/development

Changed requirement of wordpress minimal version
Merge pull request #2 from pemaxim/development

Added cache to ignore list; overview column styles for FEPS
Merge remote-tracking branch 'upstream/development' into development
Added define WPP_DEBUG_MODE to cron.php

It adds ability to use debug mode on cron job.
Example:
php -q {path} do_xml_import fa0d73f21f7e652bc7b63a04534e4107 debug_mode