Replaces a contract job's approvers (BF-7516).

Body: the full list, in approval order. Each entry names the person by userId, contactId or both (the other is looked up) and sets canApproveTime, canApprovePerDiem, canApproveExpenses and viewInvoices (omitted = false). Approvers not in the list are removed; order is the position in the list. A person must be a contact of the job's client or a team member of your company; system users, and inactive users being added, are refused. A job whose timecards need approval (timecard methods 1, 2, 5, 6, 7, 9, 11) must keep at least one approver with canApproveTime unless it is a Draft. Sending the stored list changes nothing.