Extension:Echo/echo notification table

Scheme
mysql> describe echo_notification; +--+--+--+-+-+---+ +--+--+--+-+-+---+ +--+--+--+-+-+---+ 7 rows in set (0.00 sec)
 * Field                           | Type             | Null | Key | Default | Extra |
 * notification_event              | int(10) unsigned | NO   | PRI | NULL    |       |
 * notification_user               | int(10) unsigned | NO   | PRI | NULL    |       |
 * notification_timestamp          | binary(14)       | NO   |     | NULL    |       |
 * notification_read_timestamp     | binary(14)       | YES  |     | NULL    |       |
 * notification_bundle_base        | tinyint(1)       | NO   |     | 1       |       |
 * notification_bundle_hash        | varbinary(32)    | NO   |     | NULL    |       |
 * notification_bundle_display_hash | varbinary(32)   | NO   |     | NULL    |       |