erp5_maileva_connector: Fix up naming convention

   The script is supposed to be called on portal context (or any context) and not on MailevaSOAPConnector, and it should return a MailevaSOAPConnector for a given reference.

bt5/erp5_maileva_connector/SkinTemplateItem/portal_skins/erp5_maileva_connector/Alarm_checkMailevaDocumentStatus.py

 portal = context.getPortalObject()
-maileva_connector = context.MailevaSOAPConnector_getAvailableConnector()
+maileva_connector = portal.ERP5Site_getAvailableMailevaSOAPConnector()
 
 notification_dict = maileva_connector.checkPendingNotifications()
 

bt5/erp5_maileva_connector/SkinTemplateItem/portal_skins/erp5_maileva_connector/MailevaSOAPConnector_getAvailableConnector.xml → bt5/erp5_maileva_connector/SkinTemplateItem/portal_skins/erp5_maileva_connector/ERP5Site_getAvailableMailevaSOAPConnector.xml

@@ -54,7 +54,7 @@
         </item>
         <item>
             <key> <string>id</string> </key>
-            <value> <string>MailevaSOAPConnector_getAvailableConnector</string> </value>
+            <value> <string>ERP5Site_getAvailableMailevaSOAPConnector</string> </value>
         </item>
       </dictionary>
     </pickle>

bt5/erp5_maileva_connector/SkinTemplateItem/portal_skins/erp5_maileva_connector/MailevaExchange_checkStatus.py

-maileva_connector = context.MailevaSOAPConnector_getAvailableConnector()
+maileva_connector = context.getPortalObject().ERP5Site_getAvailableMailevaSOAPConnector()
 result = maileva_connector.getPendingNotificationDetails(track_id)
 if result['status'] == "SENT":
   document = context.getFollowUpValue()

bt5/erp5_maileva_connector/SkinTemplateItem/portal_skins/erp5_maileva_connector/PDF_sendToMaileva.py

@@ -4,7 +4,7 @@ now = DateTime()
 portal = context.getPortalObject()
 
 # Do some check here
-maileva_connector = context.MailevaSOAPConnector_getAvailableConnector()
+maileva_connector = portal.ERP5Site_getAvailableMailevaSOAPConnector()
 
 today = now.toZone('UTC').asdatetime().strftime('%Y-%m-%d')
 number = str(portal.portal_ids.generateNewId(