Bug 17520: add serialsUpdate.pl to the list of regular cron jobs

Bug 17520: add serialsUpdate.pl to the list of regular cron jobs

This patch adds the job to debian package file and the examples file
in misc.

Test plan:
Add these lines to your cron file.
Check the results. (If an issue you expect passes the grace period defined
in the subscription, its status should go from Expected to Late.)

Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>