Calculate the check digit in the script

[openva]

Calculate the check digit in the script

[waldoj]

I've only tested this function on a single corporate ID.

[waldoj]

It's not possible to know which fields are corporate IDs based solely on the field name. While most of them are named *corp-id, not all of them are. For instance, in 7_merger.yaml, both of these fields are present:

- name:        merg-corp-id
  type:        A
  start:       2
  length:      7
  description: Corporate Id
- name:        merg-surv-id
  type:        A
  start:       18
  length:      7
  description: Survivor Corp Id

That said, I'm not confident that we're going to need a check digit for merg-surv-id. I'm going to proceed by operating on *corp-id fields.

[waldoj]

All that remains is to add a new bit to the if transform: stanza that calculates the checksum for any field containing corp-id, and stores it in a new field (check_digit?). That'll mean modifying the column list to add a new column...although we want to make sure that we don't then iterate over that column on our next loop through for field in current_map:.