Extension:CentralNotice/cn notice mixin params table

Schema summary
mysql> describe cn_notice_mixins; +-++--+-+-++ +-++--+-+-++ +-++--+-+-++
 * Field          | Type           | Null | Key | Default | Extra          |
 * nmxn_id        | int(11)        | NO   | PRI | NULL    | auto_increment |
 * nmxn_not_id    | int(11)        | NO   | MUL | NULL    |                |
 * nmxn_mixin_name | varbinary(255) | NO  | MUL | NULL    |                |
 * nmxn_enabled   | tinyint(1)     | NO   |     | 0       |                |