v156: Multiple definitions of osh_updated_by function

[lat9]

As reported in this Zen Cart posting, I blew it for the changes associated with #1342.

Pre-existing installations using zen_update_orders_history have that function defined in an /includes/functions/extra_function-based file. The extra functions are included by the init_general_functions.php processing which is, unfortunately, prior to the now in-core load of the functions_osh_update.php.

[lat9]

That PR just pushed swaps the load of the functions_osh_update.php with init_general_functions.php, to allow that in-core version of the function to be defined prior to the load of the extra_functions files.

Any pre-existing definition of that function will no longer load, based on that now-previous definition.

[drbyte]

Closed by #2225