Extend Ordermgr to provide an overview of parties and their roles of an order

Currently the screens of an order show only references to the following parties related to the order:

• the internal party (referenced through OrderRoles)
• the opposing party (the customer or the supplier - referenced through the OrderRoles entity)
• the creator of the order (referenced in the OrderHeader entity)
• the approver, rejecter and on-hold placer (referenced through the OrderStatus entity

But an overview of all the parties involved in the process of creation and evaluation of an order (think responsible sales-/purchase managers of both contract partners, legal counsel of both parties, etc) is not available. Nor can these kinds of players be added or changed in current feature set regarding an order.