[ic] adding tracking number to ship_notice email

[Grant]

What would be the best way to add the tracking number for a shipment to the
ship_notice email?  I'm thinking something like adding a field to certain
tables, and then adding the ability to edit that field from the UI.  If
that's the way to do it, what tables would I need to add the
"tracking_number" field to and how could I add the ability to update that
field from the order_detail page in the UI?

- Grant