Did not delete some data in DB on uninstall.

Hello,

Thank you for nice plugin. I’ve tested with installed, activated, deactivated, uninstalled and found that one data in _options table were left when uninstalled. It is antispambee_db_version option.

I see that you have uninstall() method called but you missed this option in there. Please include to delete this thing on uninstall.

Thank you.