[DOCS] Add note about new major version

Documentation/Installation/Index.rst

@@ -18,6 +18,19 @@ It requires extension “svconnector” which provides the base
 for all connector services.
 
 
+.. _installation-update-500:
+
+Updating to 5.0.0
+^^^^^^^^^^^^^^^^^
+
+Version 5.0.0 adds support for TYPO3 13 and PHP 8.4, while dropping support
+for TYPO3 11 and PHP 7.4 and 8.0.
+
+Events have been introduced to replace hooks. Existing hooks are still in place,
+but are deprecated and events should now be used instead
+(see the :ref:`svconnector manual <svconnector:developers-events>` for reference).
+
+
 .. _installation-update-400:
 
 Updating to 4.0.0