bpo-33907: Rename an IDLE module and classes. (GH-7810)


Fix-up class name duplication in PR GH-7807. Combined effect is that
module calltips and its class CallTips are now calltip and Calltip.
In module calltip_w class CallTip is now CalltipWindow.
(cherry picked from commit 9af1836664d241fec6e62955ffaa559b3a2eaf1b)

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
diff --git a/Lib/idlelib/calltip.py b/Lib/idlelib/calltip.py
index 1ff0deb..596d2bc 100644
--- a/Lib/idlelib/calltip.py
+++ b/Lib/idlelib/calltip.py
@@ -31,7 +31,7 @@
 
     def _make_tk_calltip_window(self):
         # See __init__ for usage
-        return calltip_w.Calltip(self.text)
+        return calltip_w.CalltipWindow(self.text)
 
     def _remove_calltip_window(self, event=None):
         if self.active_calltip:
@@ -44,7 +44,7 @@
         return "break"
 
     def try_open_calltip_event(self, event):
-        """Happens when it would be nice to open a Calltip, but not really
+        """Happens when it would be nice to open a calltip, but not really
         necessary, for example after an opening bracket, so function calls
         won't be made.
         """