More bug fixes for the collection interface parts checklist:
- restore the visual grouping, such that figures and their associated accessories live together in the same row (instead of all figures being in one list, and all accessories in another)
- add a border to separate said groups
- add a spacer to empty figure lists (so that things like gestalt instruction booklets or other accessories with no associated figure stay over on the right)
- fix errors seen on collection page for items in "loose" condition with figure-less instruction booklets
