Like a Subscription Request, a Subscription Change Request is used to create a new Open Sale Order,
but, it also archive a previous one at the same time.

The purpose is to change some parameters of an Open Sale Order,
and correctly created compensation movement, to ensure the resource
stock is correct.

Stop using discount resource, and reduce the quantity of the consumed software product / service

Only Sale people can create Subscription Change Request.

TODO: check how quantity precision can be defined

The only use case supported for now is changing an Instance Tree's user.

See merge request nexedi/slapos.core!629

  No need to always set those properties, while no accounting is setup.

  Let the project introduce it if they rely on those payment modes.

   Use subscription_list to calculate Balance amount for the ledger, currency, section from the list. It keeps consistency with the Entity_createDepositPaymentTransaction implementation.

   For now we rely on Base_createExternalPaymentTransactionFromOutstandingAmountAndRedirect for pay subscriptions for customer organisation because it requires update security and review the procedure and how UI will handle it.

  So we invoke directly Entity_createDepositPaymentTransaction with the organisation's subscriptions.

   Use acquisition properly.

   Same as Sale Invoice Transaction to generate payments.

   Merge Deposit and Invoice payments under the same (or nearly similar) implementation.

  Reimplement Entity_addDeposity by creating deposit from a list of subscription

  Ensure will transfer deposit to the proper organisation/person, ledger
  and currency.

  Payment Transaction must preserve website context otherwise it will
  fail over redirections later on.

   It must lead to "Contact us" page. Allow us use accounting for other configurations, so it
   allow the user generate a payment and contact us to make the wire transfer or pay from
   some non-automated system.

   Since payzen/wechat depends on specific currency, so keep default implementation generic, so it allows the user get a contact us message, so it permits the system use wire transfer or non-automatic payments, to proceed with payment.

  whenever the tests need it.

  This should be set from the test or by the user while configure payzen.

   It is more accurate to include testing data via test (on setup), otherwise it can lead to enable undesired configurations and eventually include testing data in production.

   If required, use a separated bt5 for include specific testing data.

   Since it should handle multiple *_section.

   Display a blank page is disturbing in general, so at least show a loading bar with some message.

   The currency as parameter is useful for bootstrap region specific
    tests later on, and allow reuse this script to bootstrap dev environment
    in EUR or CNY to test payments.

   Entity is more accurate since it could be used on B2B context later.

  Make it reusable so that we can inspect the balance of the user for other purposes

slapos_accounting: Entity_getDepositBalanceAmount

  Remove non required code around the topic.

  Include checkInstanceAllocationWithDeposit on tests to checks the use case
    whenever the pay the deposit is required to allocate.

  Update tests to pay precise deposit, since a more accurate use case is
    check and pay a proper amount of deposit and check if the steps are
    working properly (ie.: Subscription request stays in submitted)

In some conditions there is no name attribute on tap, so allow real fallback
to interface name.

   If the instance empty dont display green but red, indicating something is wrong.

   Clean up and minimize the configuration a bit more, so it is easy to navigate.