The module `payment_transfer` was originally meant to implement a
payment with Wire Transfer flow, which it does not exactly do since all
it does it making transactions follow the payment flow until their
`pending_msg` field's content is shown to the customer. Because of that,
other modules (`website_delivery_ups`, `website_sale_picking`) started
duplicating the base acquirer Wire Transfer to create new payment modes
such as Cash on Delivery and Pay in Store.
To better prepare for a proper dinstinction of the custom modes enabled
by other modules, this commit renames the module `payment_transfer` to
`payment_custom`.
The module `payment_transfer`'s `auto-install` key is also set to
`False` since we no longer want Wire Transfer to be the default payment
acquirer for new databases.
task-2853489
Part-of: odoo/odoo#99400
Victor Feyens
5f41f15e6b