new: Admin header bar with new support integration.
new: Help buttons located in the plugin to provide context-specific assistance
changed: Mailster related notices only show up on Mailster related pages.
fixed: campaign related conditions for "Any Campaign" now work as expected.
fixed: restoring of deleted subscribers working again.
fixed: issue where some subscribers are not able to get deleted/exported
fixed: missing object error in mailster-script
fixed: searching with quotes on the subscribers page working again
fixed: broken RSS feed URL can cause timeouts
fixed: force array when duplicating a campaign for wp_insert_post
change: do not use the $wp_filesystem global when require filesystem
added: mailster_get_user_setting and mailster_set_user_setting