Confirmation: Success and Failure pages

Problem/Motivation

Greenwich would like different text and presentation for success and failure of payments (from webforms). This seems a reasonable requirement, and would be helpful to most users.

Proposed resolution

Create different templates for success and failure. Change the theme template in the output from the confirmation controller. Add text a test field for custom message on failure as there is now for confirmation (becomes custom message for success). Also add a link to retry the payment on the failure page.

Remaining tasks

• Some default theming.

User interface changes

New presentation on confirmation return page.

API changes

New templates and additional controller for retrying.