[IMP] payment: Add information on Stripe payment acquirer kanban vignette

Purpose
=======

Stripe is now a payment acquirer that can be used to manage subscriptions, just like Authorize and Ingenico.

Specification
=============

For Stripe : add "Subscriptions" and "Save Cards" as features on the payment acquirer selection screen

addons/payment/data/payment_acquirer_data.xml

@@ -188,6 +188,8 @@
             <ul class="list-inline">
                 <li><i class="fa fa-check"/>Online Payment</li>
                 <li><i class="fa fa-check"/>Payment Status Tracking</li>
+                <li><i class="fa fa-check"/>Subscriptions</li>
+                <li><i class="fa fa-check"/>Save Cards</li>
             </ul>
         </field>
         <!--