Finish the declaration forms

For discussion: multiple charity support.

• Support multiple charities, and allow each to be configured separately (enable/disable and dates). Most complex / highest cost.
• Support multiple charities, but enforce they are all configured together: a single enable/disable, and the blurb lists all the names
• Variation: donor self-declaration configures them all together, staff can be separate (because they might receive a letter about just one charity)
• Don't support multiple charities

Answer: Don't support multiple charities - always use the default in the UI