Log Message:
Update drupal6 package to 6.16.

Drupal 6.16, 2010-03-03
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- Fixed security issues (Installation cross site scripting, Open redirection,
  Locale module cross site scripting, Blocked user session regeneration),
  see SA-CORE-2010-001.
- Better support for updated jQuery versions.
- Reduced resource usage of update.module.
- Fixed several issues relating to support of install profiles and
  distributions.
- Added a locking framework to avoid data corruption on long operations.
- Fixed a variety of other bugs.