Fix /list when no server is provided

(thanks eijebong)

src/core/commands.py

@@ -266,7 +266,7 @@ def command_list(self, args):
     if args is None:
         return self.command_help('list')
     elif args:
-        server = safeJID(args[0])
+        server = safeJID(args[0]).server
     else:
         if not isinstance(self.current_tab(), tabs.MucTab):
             return self.information('Please provide a server', 'Error')

src/tabs/muclisttab.py

@@ -20,7 +20,7 @@ class MucListTab(ListTab):
     plugin_keys = {}
 
     def __init__(self, server):
-        ListTab.__init__(self, server.full,
+        ListTab.__init__(self, server,
                          "“j”: join room.",
                          'Chatroom list on server %s (Loading)' % server,
                          (('node-part', 0), ('name', 2), ('users', 3)))