CRM-12614. Add postUpgradeMessage for 4.3.4 which warns system admins that cli.php now requires a password.

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* CRM-12614: Password required again for CLI cron
  http://issues.civicrm.org/jira/browse/CRM-12614
CRM-12614 adding empty mysql.tpl file for 4.3.4 release. Seems like this is still required in order to user postUpgradeMessage function for a release.

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* CRM-12614: Password required again for CLI cron
  http://issues.civicrm.org/jira/browse/CRM-12614
Merge pull request #764 from davecivicrm/CRM-12614

Crm 12614