frontends (xmlui): class_map is now an arg of create function: class_map was so far used as a global value, but in some cases, several XMLUI managers may be used (it's the case in Cagou's remote controllers plugins, template_xmlui is used to manage remotes). This patch set class_map as a create argument, this way it can be set with partial, and several XMLUI managers can be instanced at the same time.