Need to clear caches after running update.php

update.php should clear the caches (or, at the very least, the menu cache) after running updates.

This is imporant if, for example, the menu structure has changed. If the old one remains cached, the newly added pages are inaccessible unless the user is smart enough to clear the cache themselves.

This manifests itself as a major bug in the block modules updates. After updating the appropriate files and running update.php, the new block "configure" screens are still inaccessible. Clearing the menu cache fixes the problem.