[IMP] Added a method to retrieve the OpenERP server version
[IMP] Do not send the context for a method call if no context is defined in he proxy object
[IMP] Allow to create a proxy object which will not send context
[IMP] Added a method to retrieve the model name and id corresponding to an xml_id, depending on the server version
[FIX] The create_view method now works for OpenERP v5 and v6