LP#1743262 CC external payment requires app. code

LP#1743262 CC external payment requires app. code

1. Indicate in the CC form that the approval_code field is required,
   styled consistently with the patron edit app.

2. Prevent the form dialog from closing via Submit when no approval code
   is set.

3. Handle payment failures better by preventing the post-API code from
   running (i.e. receipt printing) when the API fails.

Signed-off-by: Bill Erickson <berickxx@gmail.com>