Reword deprecation notice to be clearer

Author: kytta

menu/menu.py

@@ -3,8 +3,9 @@
 from simple_menu.menu import *
 
 warnings.warn(
-    "Importing from 'menu' will be removed in django-simple-menu v2.3 and/or "
-    "v3.0. Use imports from 'simple_menu' package instead.",
+    "Importing from 'menu' is deprecated. Import from 'simple_menu' instead. "
+    "The old import will be removed in django-simple-menu v3, but no earlier "
+    "than on 2024-04-01.",
     DeprecationWarning,
     stacklevel=2
 )

menu/templatetags/menu.py

@@ -3,8 +3,9 @@
 from simple_menu.templatetags.simple_menu import *
 
 warnings.warn(
-    "The 'menu' template library will be removed in django-simple-menu v2.3 "
-    "and/or v3.0. Use '{% load simple_menu %}' instead.",
+    "Loading from 'menu' is deprecated. Use '{% load simple_menu %}' instead. "
+    "The old template library will be removed in django-simple-menu v3, but "
+    "no earlier than on 2024-04-01.",
     DeprecationWarning,
     stacklevel=2
 )