The installation of a new acquirer was a bit complicated : from settings,
check the acquirer, then apply (install the module) then list view of
acquirer and finally edit it in form view.
This needed to be simplified. The payment acquirers are pre-filled
in payment. From the kanban view an `Install` button installs and
redirects to the form field.
merge *ALL* the dicts
The form rendering used to receive a dict for partner information and a dict for tx information and to transmit another dict to the qweb template; now everything is done in a single dict
Martin Geubelle