Change custom name to obey preassigned_badge_types

The custom name field used to only appear for hard-coded badge types. It
now checks preassigned_badge_types instead.
Fix has_personalized_badge property

The Attendee's has_personalized_badge property now looks at
preassigned_badge_types instead of hardcoded badge types.
Merge pull request #633 from magfest/fix_custom_name

Fix custom badges