add sudden death field to sports.json

Note that not all overtime rules can be expressed in this way,
but it's a start.
sports.json: true and false don't want quotes

If they have quotes, then they both evaluate to true in boolean context.
This was breaking all of the sport setting checkboxes.
fix/cleanup checkbox handler in unserializeInputsJson

this fixes an issue where checkboxes weren't always getting unserialized