Make GlancesTextbox a new-style class

super() needs to inherit from the 'object' class.

glances/outputs/glances_curses.py

@@ -1245,15 +1245,14 @@ class GlancesCursesBrowser(_GlancesCurses):
         return True
 
 if not is_windows:
+    class GlancesTextbox(Textbox, object):
 
-    class GlancesTextbox(Textbox):
-
-        def __init__(*args, **kwargs):
-            Textbox.__init__(*args, **kwargs)
+        def __init__(self, *args, **kwargs):
+            super(GlancesTextbox, self).__init__(*args, **kwargs)
 
         def do_command(self, ch):
             if ch == 10:  # Enter
                 return 0
             if ch == 127:  # Back
                 return 8
-            return Textbox.do_command(self, ch)
+            return super(GlancesTextbox, self).do_command(ch)