The copy has nobody on it but the copier, yet it took every payer and
split row along. Its balances then had the copier owing people who cannot
see the trip, and the first save of such an expense dropped them and
shrank its total.
An expense anyone else pays for or shares now comes across as a planning
entry with its total and no payers, split or receipt lines; one that is
the copier's alone is copied whole. Assignment participants and the
legacy paid_by_user_id keep only the copier for the same reason.
Refs #2604
Maurice
64537a0224