Setup 4.2 migration notes

Author: othercorey

en/appendices/4-2-migration-guide.rst

@@ -0,0 +1,25 @@
+4.2 Migration Guide
+###################
+
+CakePHP 4.2 is an API compatible upgrade from 4.0. This page outlines the
+deprecations and features added in 4.2.
+
+
+Deprecations
+============
+
+4.2 introduces a few deprecations. All of these features will continue for the
+duration of 4.x but will be removed in 5.0. You can use the
+:ref:`upgrade tool <upgrade-tool-use>` to automate updating usage of deprecated
+features::
+
+    bin/cake upgrade rector --rules cakephp42 <path/to/app/src>
+
+Behavior Changes
+================
+
+While the following changes do not change the signature of any methods they do
+change the semantics or behavior of methods.
+
+New Features
+============

en/appendices/migration-guides.rst

@@ -2,8 +2,9 @@ Migration Guides
 ################
 
 Migration guides contain information regarding the new features introduced in
-each version and the migration path between 3.x and 4.x. 
+each version and the migration path between 3.x and 4.x.
 
 * :doc:`./4-0-upgrade-guide`
 * :doc:`./4-0-migration-guide`
 * :doc:`./4-1-migration-guide`
+* :doc:`./4-2-migration-guide`