Populate the TZ tables on install

Default installs don't populate the TZ tables on installation. These should be populated at package install time.

Because the error is less than helpful, it's not intuitive what the fix is:

mysql> select convert_tz(now(), 'SYSTEM', 'US/Eastern');
+-------------------------------------------+
| convert_tz(now(), 'SYSTEM', 'US/Eastern') |
+-------------------------------------------+
| NULL |
+-------------------------------------------+
1 row in set (0.00 sec)

So it'd be helpful if the tables were populated by default.