Add the ban date to the blacklist table

[erikyo]

It shouldn't be a problem to add the date to the meta as well, and for statistical issues it might be worth having

cf7-antispam/engine/CF7_AntiSpam_Activator.php

Lines 187 to 193 in 1e77b7e

	$cf7a_database = "CREATE TABLE IF NOT EXISTS `{$table_blacklist}` (
	`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
	`ip` varchar(45) NOT NULL,
	`status` int(10) unsigned DEFAULT NULL,
	`meta` longtext,
	PRIMARY KEY (`id`),
	UNIQUE KEY `id` (`ip`)

rel. https://wordpress.org/support/topic/some-blacklist-questions/#post-17470371