DB update fails to run on sites that ran the long since removed 7200 db update

An old DB update numbered 7200 was removed a long time ago (https://github.com/thinkshout/commerce_iats/commit/e35c0c41803bb4175a269...). Sites that ran that update before it was removed have the schema for commerce_iats set to 7200. This prevents the more recent update numbered 7000 from running.

We should update the existing 7000 update to be 7201 and add a check for existence of the db column before running _commerce_iats_initialize_line_item_property(). 72XX is the proper numbers for a 2.x module too.